merge mozilla-inbound to mozilla-central a=merge

accessible/aom/AccessibleNode.cpp

@@ -154,6 +154,7 @@ AccessibleNode::Get(JSContext* aCX, const nsAString& aAttribute,
 {
   if (!mIntl) {
     aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
+    return;
   }
 
   nsCOMPtr<nsIPersistentProperties> attrs = mIntl->Attributes();
@@ -163,6 +164,7 @@ AccessibleNode::Get(JSContext* aCX, const nsAString& aAttribute,
   JS::Rooted<JS::Value> jsval(aCX);
   if (!ToJSValue(aCX, value, &jsval)) {
     aRv.Throw(NS_ERROR_UNEXPECTED);
+    return;
   }
 
   aValue.set(jsval);

accessible/tests/browser/e10s/browser_caching_name.js

@@ -392,7 +392,7 @@ function* testSubtreeRule(browser, target, rule, expected) {
   yield ContentTask.spawn(browser, target.id, id => {
     let elm = content.document.getElementById(id);
     while (elm.firstChild) {
-      elm.removeChild(elm.firstChild);
+      elm.firstChild.remove();
     }
   });
   yield updateAccessibleIfNeeded(onEvent, target);

accessible/tests/browser/e10s/browser_treeupdate_doc.js

@@ -157,7 +157,7 @@ addAccessibleTask(`
   yield ContentTask.spawn(browser, {}, () => {
     // Remove HTML element.
     let docNode = content.document.getElementById('iframe').contentDocument;
-    docNode.removeChild(docNode.firstChild);
+    docNode.firstChild.remove();
   });
   let event = yield reorderEventPromise;
 
@@ -235,7 +235,7 @@ addAccessibleTask(`
     let docEl =
       content.document.getElementById('iframe').contentDocument.documentElement;
     // Remove aftermath of this test before next test starts.
-    docEl.removeChild(docEl.firstChild);
+    docEl.firstChild.remove();
   });
   // Make sure reorder event was fired and that the input was removed.
   yield reorderEventPromise;

accessible/tests/browser/e10s/browser_treeupdate_optgroup.js

@@ -56,7 +56,7 @@ addAccessibleTask('<select id="select"></select>', function*(browser, accDoc) {
   // Remove grouping from combobox
   yield ContentTask.spawn(browser, {}, () => {
     let contentSelect = content.document.getElementById('select');
-    contentSelect.removeChild(contentSelect.firstChild);
+    contentSelect.firstChild.remove();
   });
   yield onEvent;
 

accessible/tests/mochitest/events/test_mutation.html

@@ -414,8 +414,8 @@
         var l1 = doc.firstChild;
         this.target = l1.firstChild;
         var l2 = doc.lastChild;
-        l1.DOMNode.removeChild(l1.DOMNode.firstChild);
-        l2.DOMNode.removeChild(l2.DOMNode.firstChild);
+        l1.DOMNode.firstChild.remove();
+        l2.DOMNode.firstChild.remove();
       }
 
       this.check = function hideHideNDestroyDoc_check()

accessible/tests/mochitest/events/test_text.html

@@ -51,7 +51,7 @@
       this.invoke = function removeChildSpan_invoke()
       {
         // remove HTML span, a first child of the node
-        this.DOMNode.removeChild(this.DOMNode.firstChild);
+        this.DOMNode.firstChild.remove();
       }
 
       this.getID = function removeChildSpan_getID()
@@ -162,7 +162,7 @@
             this.DOMNode.removeChild(this.DOMNode.lastChild);
         } else {
           while (this.DOMNode.firstChild)
-            this.DOMNode.removeChild(this.DOMNode.firstChild);
+            this.DOMNode.firstChild.remove();
         }
       }
 

accessible/tests/mochitest/name/markup.js

@@ -316,7 +316,7 @@ function testNameForSubtreeRule(aElm, aRule)
   waitForEvent(EVENT_REORDER, aElm, gTestIterator.iterateNext, gTestIterator);
 
   while (aElm.firstChild)
-    aElm.removeChild(aElm.firstChild);
+    aElm.firstChild.remove();
 }
 
 /**

accessible/tests/mochitest/treeupdate/test_doc.html

@@ -266,7 +266,7 @@
 
         // Remove HTML element.
         var docNode = getDocNode(aID);
-        docNode.removeChild(docNode.firstChild);
+        docNode.firstChild.remove();
       }
 
       this.getID = function removeHTMLFromIFrameDoc_getID()

accessible/tests/mochitest/treeupdate/test_general.html

@@ -64,7 +64,7 @@
 
       this.invoke = function removeRemove_invoke()
       {
-        getNode(aContainer).removeChild(getNode(aContainer).firstChild);
+        getNode(aContainer).firstChild.remove();
       }
 
       this.finalCheck = function removeRemove_finalCheck()

accessible/tests/mochitest/treeupdate/test_optgroup.html

@@ -77,7 +77,7 @@
       this.invoke = function removeOptGroup_invoke()
       {
         this.option1Node = this.selectNode.firstChild.firstChild;
-        this.selectNode.removeChild(this.selectNode.firstChild);
+        this.selectNode.firstChild.remove();
       }
 
       this.eventSeq = [

browser/base/content/browser-ctrlTab.js

@@ -241,7 +241,7 @@ var ctrlTab = {
     aPreview._tab = aTab;
 
     if (aPreview.firstChild)
-      aPreview.removeChild(aPreview.firstChild);
+      aPreview.firstChild.remove();
     if (aTab) {
       let canvasWidth = this.canvasWidth;
       let canvasHeight = this.canvasHeight;

browser/base/content/browser-fxaccounts.js

@@ -330,7 +330,7 @@ var gFxAccounts = {
   populateSendTabToDevicesMenu(devicesPopup, url, title) {
     // remove existing menu items
     while (devicesPopup.hasChildNodes()) {
-      devicesPopup.removeChild(devicesPopup.firstChild);
+      devicesPopup.firstChild.remove();
     }
 
     const fragment = document.createDocumentFragment();

browser/base/content/browser-places.js

@@ -746,7 +746,7 @@ HistoryMenu.prototype = {
 
     // remove existing menu items
     while (undoPopup.hasChildNodes())
-      undoPopup.removeChild(undoPopup.firstChild);
+      undoPopup.firstChild.remove();
 
     // no restorable tabs, so make sure menu is disabled, and return
     if (this._getClosedTabCount() == 0) {
@@ -782,7 +782,7 @@ HistoryMenu.prototype = {
 
     // remove existing menu items
     while (undoPopup.hasChildNodes())
-      undoPopup.removeChild(undoPopup.firstChild);
+      undoPopup.firstChild.remove();
 
     // no restorable windows, so make sure menu is disabled, and return
     if (SessionStore.getClosedWindowCount() == 0) {

browser/base/content/pageinfo/pageInfo.js

@@ -418,7 +418,7 @@ function resetPageInfo(args) {
   /* Reset Feeds Tab */
   var feedListbox = document.getElementById("feedListbox");
   while (feedListbox.firstChild)
-    feedListbox.removeChild(feedListbox.firstChild);
+    feedListbox.firstChild.remove();
 
   /* Call registered overlay reset functions */
   onResetRegistry.forEach(function(func) { func(); });

browser/base/content/pageinfo/security.js

@@ -306,7 +306,7 @@ function setText(id, value) {
     element.value = value;
   else {
     if (element.hasChildNodes())
-      element.removeChild(element.firstChild);
+      element.firstChild.remove();
     var textNode = document.createTextNode(value);
     element.appendChild(textNode);
   }

browser/base/content/utilityOverlay.js

@@ -490,7 +490,7 @@ function createUserContextMenu(event, {
                                         useAccessKeys = true
                                       } = {}) {
   while (event.target.hasChildNodes()) {
-    event.target.removeChild(event.target.firstChild);
+    event.target.firstChild.remove();
   }
 
   let bundle = document.getElementById("bundle_browser");

browser/components/customizableui/CustomizableWidgets.jsm

@@ -244,12 +244,12 @@ const CustomizableWidgets = [
 
       let recentlyClosedTabs = doc.getElementById("PanelUI-recentlyClosedTabs");
       while (recentlyClosedTabs.firstChild) {
-        recentlyClosedTabs.removeChild(recentlyClosedTabs.firstChild);
+        recentlyClosedTabs.firstChild.remove();
       }
 
       let recentlyClosedWindows = doc.getElementById("PanelUI-recentlyClosedWindows");
       while (recentlyClosedWindows.firstChild) {
-        recentlyClosedWindows.removeChild(recentlyClosedWindows.firstChild);
+        recentlyClosedWindows.firstChild.remove();
       }
 
       let utils = RecentlyClosedTabsAndWindowsMenuUtils;

browser/components/customizableui/content/panelUI.js

@@ -492,7 +492,7 @@ const PanelUI = {
 
     // Remove all buttons from the view
     while (items.firstChild) {
-      items.removeChild(items.firstChild);
+      items.firstChild.remove();
     }
 
     // Add the current set of menuitems of the Help menu to this view

browser/components/feeds/FeedWriter.js

@@ -173,7 +173,7 @@ FeedWriter.prototype = {
     let element = this._document.getElementById(id);
     let textNode = text.createDocumentFragment(element);
     while (element.hasChildNodes())
-      element.removeChild(element.firstChild);
+      element.firstChild.remove();
     element.appendChild(textNode);
     if (text.base) {
       element.setAttributeNS(XML_NS, "base", text.base.spec);

browser/components/migration/content/migration.js

@@ -185,7 +185,7 @@ var MigrationWizard = { /* exported MigrationWizard */
 
     var profiles = document.getElementById("profiles");
     while (profiles.hasChildNodes())
-      profiles.removeChild(profiles.firstChild);
+      profiles.firstChild.remove();
 
     // Note that this block is still reached even if the user chose 'From File'
     // and we canceled the dialog.  When that happens, _migrator will be null.
@@ -225,7 +225,7 @@ var MigrationWizard = { /* exported MigrationWizard */
   onImportItemsPageShow() {
     var dataSources = document.getElementById("dataSources");
     while (dataSources.hasChildNodes())
-      dataSources.removeChild(dataSources.firstChild);
+      dataSources.firstChild.remove();
 
     var items = this._migrator.getMigrateData(this._selectedProfile, this._autoMigrate);
     for (var i = 0; i < 16; ++i) {
@@ -367,7 +367,7 @@ var MigrationWizard = { /* exported MigrationWizard */
   _listItems(aID) {
     var items = document.getElementById(aID);
     while (items.hasChildNodes())
-      items.removeChild(items.firstChild);
+      items.firstChild.remove();
 
     var itemID;
     for (var i = 0; i < 16; ++i) {

browser/components/places/content/browserPlacesViews.js

@@ -1011,7 +1011,7 @@ PlacesToolbar.prototype = {
 
     this._openedMenuButton = null;
     while (this._rootElt.hasChildNodes()) {
-      this._rootElt.removeChild(this._rootElt.firstChild);
+      this._rootElt.firstChild.remove();
     }
 
     let cc = this._resultNode.childCount;
@@ -1952,7 +1952,7 @@ PlacesPanelMenuView.prototype = {
 
     // Container is the toolbar itself.
     while (this._rootElt.hasChildNodes()) {
-      this._rootElt.removeChild(this._rootElt.firstChild);
+      this._rootElt.firstChild.remove();
     }
 
     for (let i = 0; i < this._resultNode.childCount; ++i) {

browser/components/places/content/places.js

@@ -419,7 +419,7 @@ var PlacesOrganizer = {
 
     // Remove existing menu items.  Last item is the restoreFromFile item.
     while (restorePopup.childNodes.length > 1)
-      restorePopup.removeChild(restorePopup.firstChild);
+      restorePopup.firstChild.remove();
 
     Task.spawn(function* () {
       let backupFiles = yield PlacesBackups.getBackupFiles();
@@ -1007,7 +1007,7 @@ var ViewMenu = {
       return endElement;
     }
     while (popup.hasChildNodes()) {
-      popup.removeChild(popup.firstChild);
+      popup.firstChild.remove();
     }
     return null;
   },

browser/components/preferences/blocklists.js

@@ -81,7 +81,7 @@ var gBlocklistManager = {
 
     let blocklistsText = document.getElementById("blocklistsText");
     while (blocklistsText.hasChildNodes()) {
-      blocklistsText.removeChild(blocklistsText.firstChild);
+      blocklistsText.firstChild.remove();
     }
     blocklistsText.appendChild(document.createTextNode(params.introText));
 

browser/components/preferences/in-content/advanced.js

@@ -557,7 +557,7 @@ var gAdvancedPane = {
 
     var list = document.getElementById("offlineAppsList");
     while (list.firstChild) {
-      list.removeChild(list.firstChild);
+      list.firstChild.remove();
     }
 
     var groups;

browser/components/preferences/languages.js

@@ -97,7 +97,7 @@ var gLanguagesDialog = {
   _buildAvailableLanguageList() {
     var availableLanguagesPopup = document.getElementById("availableLanguagesPopup");
     while (availableLanguagesPopup.hasChildNodes())
-      availableLanguagesPopup.removeChild(availableLanguagesPopup.firstChild);
+      availableLanguagesPopup.firstChild.remove();
 
     // Sort the list of languages by name
     this._availableLanguagesList.sort(function(a, b) {
@@ -119,7 +119,7 @@ var gLanguagesDialog = {
 
   readAcceptLanguages() {
     while (this._activeLanguages.hasChildNodes())
-      this._activeLanguages.removeChild(this._activeLanguages.firstChild);
+      this._activeLanguages.firstChild.remove();
 
     var selectedIndex = 0;
     var preference = document.getElementById("intl.accept_languages");

browser/components/preferences/permissions.js

@@ -218,7 +218,7 @@ var gPermissionManager = {
 
     var permissionsText = document.getElementById("permissionsText");
     while (permissionsText.hasChildNodes())
-      permissionsText.removeChild(permissionsText.firstChild);
+      permissionsText.firstChild.remove();
     permissionsText.appendChild(document.createTextNode(aParams.introText));
 
     document.title = aParams.windowTitle;

browser/components/syncedtabs/SyncedTabsDeckView.js

@@ -100,7 +100,7 @@ SyncedTabsDeckView.prototype = {
 
   _clearChilden() {
     while (this.container.firstChild) {
-      this.container.removeChild(this.container.firstChild);
+      this.container.firstChild.remove();
     }
   },
 

browser/components/syncedtabs/TabListView.js

@@ -169,7 +169,7 @@ TabListView.prototype = {
   _clearChilden(node) {
     let parent = node || this.container;
     while (parent.firstChild) {
-      parent.removeChild(parent.firstChild);
+      parent.firstChild.remove();
     }
   },
 

browser/components/uitour/UITour.jsm

@@ -1236,7 +1236,7 @@ this.UITour = {
       // Remove all the children of the notice (rating container
       // and the flex).
       while (notice.firstChild) {
-        notice.removeChild(notice.firstChild);
+        notice.firstChild.remove();
       }
 
       // Make sure that we have a valid URL. If we haven't, do not open the engagement page.

browser/extensions/mortar/ppapi/generators/idl_gen_rpc.py

@@ -43,6 +43,7 @@ customAPIs = {
   ('PPB_PDF', 'SetAccessibilityPageInfo', 'text_runs'): { 'arraySize': 'page_info->text_run_count' },
   ('PPB_PDF', 'SetAccessibilityPageInfo', 'chars'): { 'arraySize': 'page_info->char_count' },
   ('PPB_TCPSocket_Private', 'Write', 'buffer'): { 'array': True, 'arrayType': 'uint8_t', 'arraySize': 'bytes_to_write' },
+  ('PPP_Printing_Dev', 'PrintPages', 'page_ranges'): { 'array': True, 'arraySize': None },
 }
 def getCustom(interface, member, param):
   def matches(pattern, value):
@@ -335,7 +336,10 @@ class RPCGen(object):
     for param in callnode.GetListOf('Param'):
       mode = self.cgen.GetParamMode(param)
       ptype, pname, parray, pspec = self.cgen.GetComponents(param, release, "store")
-      out += '  ' + self.cgen.Compose(ptype, pname, parray, pspec, '', func_as_ptr=True,
+      prefix = ''
+      if getCustom(iface.GetName(), node.GetName(), param.GetName()).get("array"):
+        prefix = '*'
+      out += '  ' + self.cgen.Compose(ptype, pname, parray, pspec, prefix, func_as_ptr=True,
               include_name=True, unsized_as_ptr=True) + ';\n'
       if mode == 'out':
         if len(parray) > 0:
@@ -359,7 +363,8 @@ class RPCGen(object):
       mode = self.cgen.GetParamMode(param)
       ntype, mode = self.cgen.GetRootTypeMode(param, release, mode)
       ptype, pname, parray, pspec = self.cgen.GetComponents(param, release, mode)
-      if mode == 'out' or ntype == 'Struct' or (mode == 'constptr_in' and ntype == 'TypeValue'):
+      isArray = getCustom(iface.GetName(), node.GetName(), param.GetName()).get("array")
+      if (mode == 'out' or ntype == 'Struct' or (mode == 'constptr_in' and ntype == 'TypeValue')) and not isArray:
         pname = '&' + pname
       pname = '(' + self.cgen.Compose(ptype, pname, parray, pspec, '', func_as_ptr=True,
               include_name=False, unsized_as_ptr=True) + ')' + pname

browser/extensions/mortar/ppapi/out/rpc.cc

@@ -237,74 +237,6 @@ inline bool PP_ToBool(PP_Bool b) {
 
 #endif  /* __cplusplus */
 
-/* pp_point.idl */
-/**
- * @addtogroup Structs
- * @{
- */
-/**
- * The PP_Point structure defines the integer x and y coordinates of a point.
- */
-struct PP_Point {
-  /**
-   * This value represents the horizontal coordinate of a point, starting with 0
-   * as the left-most coordinate.
-   */
-  int32_t x;
-  /**
-   * This value represents the vertical coordinate of a point, starting with 0
-   * as the top-most coordinate.
-   */
-  int32_t y;
-};
-PP_COMPILE_ASSERT_STRUCT_SIZE_IN_BYTES(PP_Point, 8);
-
-/**
- * The PP_FloatPoint structure defines the floating-point x and y coordinates
- * of a point.
- */
-struct PP_FloatPoint {
-  float x;
-  float y;
-};
-PP_COMPILE_ASSERT_STRUCT_SIZE_IN_BYTES(PP_FloatPoint, 8);
-/**
- * @}
- */
-
-/**
- * @addtogroup Functions
- * @{
- */
-
-/**
- * PP_MakePoint() creates a <code>PP_Point</code> given the x and y coordinates
- * as int32_t values.
- *
- * @param[in] x An int32_t value representing a horizontal coordinate of a
- * point, starting with 0 as the left-most coordinate.
- * @param[in] y An int32_t value representing a vertical coordinate of a point,
- * starting with 0 as the top-most coordinate.
- *
- * @return A <code>PP_Point</code> structure.
- */
-PP_INLINE struct PP_Point PP_MakePoint(int32_t x, int32_t y) {
-  struct PP_Point ret;
-  ret.x = x;
-  ret.y = y;
-  return ret;
-}
-
-PP_INLINE struct PP_FloatPoint PP_MakeFloatPoint(float x, float y) {
-  struct PP_FloatPoint ret;
-  ret.x = x;
-  ret.y = y;
-  return ret;
-}
-/**
- * @}
- */
-
 /* pp_size.idl */
 /**
  * @addtogroup Structs
@@ -373,6 +305,74 @@ PP_INLINE struct PP_FloatSize PP_MakeFloatSize(float w, float h) {
 /**
  * @}
  */
+/* pp_point.idl */
+/**
+ * @addtogroup Structs
+ * @{
+ */
+/**
+ * The PP_Point structure defines the integer x and y coordinates of a point.
+ */
+struct PP_Point {
+  /**
+   * This value represents the horizontal coordinate of a point, starting with 0
+   * as the left-most coordinate.
+   */
+  int32_t x;
+  /**
+   * This value represents the vertical coordinate of a point, starting with 0
+   * as the top-most coordinate.
+   */
+  int32_t y;
+};
+PP_COMPILE_ASSERT_STRUCT_SIZE_IN_BYTES(PP_Point, 8);
+
+/**
+ * The PP_FloatPoint structure defines the floating-point x and y coordinates
+ * of a point.
+ */
+struct PP_FloatPoint {
+  float x;
+  float y;
+};
+PP_COMPILE_ASSERT_STRUCT_SIZE_IN_BYTES(PP_FloatPoint, 8);
+/**
+ * @}
+ */
+
+/**
+ * @addtogroup Functions
+ * @{
+ */
+
+/**
+ * PP_MakePoint() creates a <code>PP_Point</code> given the x and y coordinates
+ * as int32_t values.
+ *
+ * @param[in] x An int32_t value representing a horizontal coordinate of a
+ * point, starting with 0 as the left-most coordinate.
+ * @param[in] y An int32_t value representing a vertical coordinate of a point,
+ * starting with 0 as the top-most coordinate.
+ *
+ * @return A <code>PP_Point</code> structure.
+ */
+PP_INLINE struct PP_Point PP_MakePoint(int32_t x, int32_t y) {
+  struct PP_Point ret;
+  ret.x = x;
+  ret.y = y;
+  return ret;
+}
+
+PP_INLINE struct PP_FloatPoint PP_MakeFloatPoint(float x, float y) {
+  struct PP_FloatPoint ret;
+  ret.x = x;
+  ret.y = y;
+  return ret;
+}
+/**
+ * @}
+ */
+
 /* pp_rect.idl */
 /**
  * @addtogroup Structs
@@ -49238,14 +49238,22 @@ char* Call_PPP_Printing_Dev_PrintPages(const PPP_Printing_Dev* _interface, JSONI
   PP_Instance instance;
   iterator.skip();
   FromJSON_PP_Instance(iterator, instance);
-  struct PP_PrintPageNumberRange_Dev page_ranges;
+  struct PP_PrintPageNumberRange_Dev *page_ranges;
   iterator.skip();
-  FromJSON_PP_PrintPageNumberRange_Dev(iterator, page_ranges);
+
+  {
+    size_t children = iterator.expectArrayAndGotoFirstItem();
+    page_ranges = new struct PP_PrintPageNumberRange_Dev[children];
+    for (uint32_t _n = 0; _n < children; ++_n) {
+      FromJSON_PP_PrintPageNumberRange_Dev(iterator, (page_ranges)[_n]);
+    }
+    // FIXME Null out remaining items?
+  }
   uint32_t page_range_count;
   iterator.skip();
   FromJSON_uint32_t(iterator, page_range_count);
   int32_t rval;
-  rval = _interface->PrintPages((PP_Instance )instance, (const struct PP_PrintPageNumberRange_Dev* )&page_ranges, (uint32_t )page_range_count);
+  rval = _interface->PrintPages((PP_Instance )instance, (const struct PP_PrintPageNumberRange_Dev* )page_ranges, (uint32_t )page_range_count);
   return strdup(ToString_PP_Resource(rval).c_str());
 }
 char* Call_PPP_Printing_Dev_End(const PPP_Printing_Dev* _interface, JSONIterator& iterator) {

browser/extensions/pdfjs/content/web/viewer.js

@@ -3898,7 +3898,7 @@ var PDFAttachmentViewer = function PDFAttachmentViewerClosure() {
    this.attachments = null;
    var container = this.container;
    while (container.firstChild) {
-    container.removeChild(container.firstChild);
+    container.firstChild.remove();
    }
    if (!keepRenderedCapability) {
     this._renderedCapability = pdfjsLib.createPromiseCapability();
@@ -4598,7 +4598,7 @@ var PDFOutlineViewer = function PDFOutlineViewerClosure() {
    this.lastToggleIsShow = true;
    var container = this.container;
    while (container.firstChild) {
-    container.removeChild(container.firstChild);
+    container.firstChild.remove();
    }
   },
   _dispatchEvent: function PDFOutlineViewer_dispatchEvent(outlineCount) {

build/clang-plugin/Checks.inc

@@ -10,6 +10,7 @@ CHECK(ExplicitImplicitChecker, "implicit-constructor")
 CHECK(ExplicitOperatorBoolChecker, "explicit-operator-bool")
 CHECK(KungFuDeathGripChecker, "kungfu-death-grip")
 CHECK(MustOverrideChecker, "must-override")
+CHECK(MustReturnFromCallerChecker, "must-return-from-caller")
 CHECK(MustUseChecker, "must-use")
 CHECK(NaNExprChecker, "nan-expr")
 CHECK(NeedsNoVTableTypeChecker, "needs-no-vtable-type")

build/clang-plugin/ChecksIncludes.inc

@@ -11,6 +11,7 @@
 #include "ExplicitOperatorBoolChecker.h"
 #include "KungFuDeathGripChecker.h"
 #include "MustOverrideChecker.h"
+#include "MustReturnFromCallerChecker.h"
 #include "MustUseChecker.h"
 #include "NaNExprChecker.h"
 #include "NeedsNoVTableTypeChecker.h"

build/clang-plugin/CustomMatchers.h

@@ -231,6 +231,11 @@ AST_MATCHER(CXXMethodDecl, isNonVirtual) {
   const CXXMethodDecl *Decl = Node.getCanonicalDecl();
   return Decl && !Decl->isVirtual();
 }
+
+AST_MATCHER(FunctionDecl, isMozMustReturnFromCaller) {
+  const FunctionDecl *Decl = Node.getCanonicalDecl();
+  return Decl && hasCustomAnnotation(Decl, "moz_must_return_from_caller");
+}
 }
 }
 

build/clang-plugin/MustReturnFromCallerChecker.cpp

@@ -0,0 +1,105 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "MustReturnFromCallerChecker.h"
+#include "CustomMatchers.h"
+
+void MustReturnFromCallerChecker::registerMatchers(MatchFinder* AstMatcher) {
+  // Look for a call to a MOZ_MUST_RETURN_FROM_CALLER function
+  AstMatcher->addMatcher(callExpr(callee(functionDecl(isMozMustReturnFromCaller())),
+                                  anyOf(hasAncestor(lambdaExpr().bind("containing-lambda")),
+                                        hasAncestor(functionDecl().bind("containing-func")))).bind("call"),
+                         this);
+}
+
+void MustReturnFromCallerChecker::check(
+    const MatchFinder::MatchResult& Result) {
+  const auto *ContainingLambda =
+    Result.Nodes.getNodeAs<LambdaExpr>("containing-lambda");
+  const auto *ContainingFunc =
+    Result.Nodes.getNodeAs<FunctionDecl>("containing-func");
+  const auto *Call = Result.Nodes.getNodeAs<CallExpr>("call");
+
+  Stmt *Body = nullptr;
+  if (ContainingLambda) {
+    Body = ContainingLambda->getBody();
+  } else if (ContainingFunc) {
+    Body = ContainingFunc->getBody();
+  } else {
+    return;
+  }
+  assert(Body && "Should have a body by this point");
+
+  // Generate the CFG for the enclosing function or decl.
+  CFG::BuildOptions Options;
+  std::unique_ptr<CFG> TheCFG =
+    CFG::buildCFG(nullptr, Body, Result.Context, Options);
+  if (!TheCFG) {
+    return;
+  }
+
+  // Determine which block in the CFG we want to look at the successors of.
+  StmtToBlockMap BlockMap(TheCFG.get(), Result.Context);
+  size_t CallIndex;
+  const auto *Block = BlockMap.blockContainingStmt(Call, &CallIndex);
+  assert(Block && "This statement should be within the CFG!");
+
+  if (!immediatelyReturns(Block, Result.Context, CallIndex + 1)) {
+    diag(Call->getLocStart(),
+         "You must immediately return after calling this function",
+         DiagnosticIDs::Error);
+  }
+}
+
+bool
+MustReturnFromCallerChecker::immediatelyReturns(RecurseGuard<const CFGBlock *> Block,
+                                                ASTContext *TheContext,
+                                                size_t FromIdx) {
+  if (Block.isRepeat()) {
+    return false;
+  }
+
+  for (size_t I = FromIdx; I < Block->size(); ++I) {
+    Optional<CFGStmt> S = (*Block)[I].getAs<CFGStmt>();
+    if (!S) {
+      continue;
+    }
+
+    auto AfterTrivials = IgnoreTrivials(S->getStmt());
+
+    // If we are looking at a ConstructExpr, a DeclRefExpr or a MemberExpr it's
+    // OK to use them after a call to a MOZ_MUST_RETURN_FROM_CALLER function.
+    // It is also, of course, OK to look at a ReturnStmt.
+    if (isa<ReturnStmt>(AfterTrivials) ||
+        isa<CXXConstructExpr>(AfterTrivials) ||
+        isa<DeclRefExpr>(AfterTrivials) ||
+        isa<MemberExpr>(AfterTrivials)) {
+      continue;
+    }
+
+    // It's also OK to call any function or method which is annotated with
+    // MOZ_MAY_CALL_AFTER_MUST_RETURN. We consider all CXXConversionDecls
+    // to be MOZ_MAY_CALL_AFTER_MUST_RETURN (like operator T*()).
+    if (auto CE = dyn_cast<CallExpr>(AfterTrivials)) {
+      auto Callee = CE->getDirectCallee();
+      if (Callee && hasCustomAnnotation(Callee, "moz_may_call_after_must_return")) {
+        continue;
+      }
+
+      if (Callee && isa<CXXConversionDecl>(Callee)) {
+        continue;
+      }
+    }
+
+    // Otherwise, this expression is problematic.
+    return false;
+  }
+
+  for (auto Succ = Block->succ_begin(); Succ != Block->succ_end(); ++Succ) {
+    if (!immediatelyReturns(Block.recurse(*Succ), TheContext, 0)) {
+      return false;
+    }
+  }
+  return true;
+}

build/clang-plugin/MustReturnFromCallerChecker.h

@@ -0,0 +1,26 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef MustReturnFromCallerChecker_h__
+#define MustReturnFromCallerChecker_h__
+
+#include "plugin.h"
+#include "Utils.h"
+#include "RecurseGuard.h"
+#include "StmtToBlockMap.h"
+
+class MustReturnFromCallerChecker : public BaseCheck {
+public:
+  MustReturnFromCallerChecker(StringRef CheckName,
+                              ContextType *Context = nullptr)
+    : BaseCheck(CheckName, Context) {}
+  void registerMatchers(MatchFinder* AstMatcher) override;
+  void check(const MatchFinder::MatchResult &Result) override;
+private:
+  bool immediatelyReturns(RecurseGuard<const CFGBlock *> Block,
+                          ASTContext *TheContext,
+                          size_t FromIdx);
+};
+
+#endif

build/clang-plugin/RecurseGuard.h

@@ -0,0 +1,63 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef RecurseGuard_h__
+#define RecurseGuard_h__
+
+#include "Utils.h"
+
+// This class acts as a tracker for avoiding infinite recursion when traversing
+// chains in CFGs etc.
+//
+// Constructing a RecurseGuard sets up a shared backing store which tracks the
+// currently observed objects. Whenever recursing, use RecurseGuard.recurse(T)
+// to construct another RecurseGuard with the same backing store.
+//
+// The RecurseGuard object will unregister its object when it is destroyed, and
+// has a method `isRepeat()` which will return `true` if the item was already
+// seen.
+template<typename T>
+class RecurseGuard {
+public:
+  RecurseGuard(T Thing) : Thing(Thing), Set(new DenseSet<T>()), Repeat(false) {
+    Set->insert(Thing);
+  }
+  RecurseGuard(T Thing, std::shared_ptr<DenseSet<T>>& Set)
+    : Thing(Thing), Set(Set), Repeat(false) {
+    Repeat = !Set->insert(Thing).second;
+  }
+  RecurseGuard(const RecurseGuard &) = delete;
+  RecurseGuard(RecurseGuard && Other)
+    : Thing(Other.Thing), Set(Other.Set), Repeat(Other.Repeat) {
+    Other.Repeat = true;
+  }
+  ~RecurseGuard() {
+    if (!Repeat) {
+      Set->erase(Thing);
+    }
+  }
+
+  bool isRepeat() { return Repeat; }
+
+  T get() { return Thing; }
+
+  operator T() {
+    return Thing;
+  }
+
+  T operator ->() {
+    return Thing;
+  }
+
+  RecurseGuard recurse(T NewThing) {
+    return RecurseGuard(NewThing, Set);
+  }
+
+private:
+  T Thing;
+  std::shared_ptr<DenseSet<T>> Set;
+  bool Repeat;
+};
+
+#endif // RecurseGuard_h__

build/clang-plugin/StmtToBlockMap.h

@@ -0,0 +1,86 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef StmtToBlockMap_h__
+#define StmtToBlockMap_h__
+
+#include "Utils.h"
+
+// This method is copied from clang-tidy's ExprSequence.cpp.
+//
+// Returns the Stmt nodes that are parents of 'S', skipping any potential
+// intermediate non-Stmt nodes.
+//
+// In almost all cases, this function returns a single parent or no parents at
+// all.
+inline SmallVector<const Stmt *, 1> getParentStmts(const Stmt *S,
+                                                   ASTContext *Context) {
+  SmallVector<const Stmt *, 1> Result;
+
+  ASTContext::DynTypedNodeList Parents = Context->getParents(*S);
+
+  SmallVector<ast_type_traits::DynTypedNode, 1> NodesToProcess(Parents.begin(),
+                                                               Parents.end());
+
+  while (!NodesToProcess.empty()) {
+    ast_type_traits::DynTypedNode Node = NodesToProcess.back();
+    NodesToProcess.pop_back();
+
+    if (const auto *S = Node.get<Stmt>()) {
+      Result.push_back(S);
+    } else {
+      Parents = Context->getParents(Node);
+      NodesToProcess.append(Parents.begin(), Parents.end());
+    }
+  }
+
+  return Result;
+}
+
+// This class is a modified version of the class from clang-tidy's ExprSequence.cpp
+//
+// Maps `Stmt`s to the `CFGBlock` that contains them. Some `Stmt`s may be
+// contained in more than one `CFGBlock`; in this case, they are mapped to the
+// innermost block (i.e. the one that is furthest from the root of the tree).
+// An optional outparameter provides the index into the block where the `Stmt`
+// was found.
+class StmtToBlockMap {
+public:
+  // Initializes the map for the given `CFG`.
+  StmtToBlockMap(const CFG *TheCFG, ASTContext *TheContext) : Context(TheContext) {
+    for (const auto *B : *TheCFG) {
+      for (size_t I = 0; I < B->size(); ++I) {
+        if (Optional<CFGStmt> S = (*B)[I].getAs<CFGStmt>()) {
+          Map[S->getStmt()] = std::make_pair(B, I);
+        }
+      }
+    }
+  }
+
+  // Returns the block that S is contained in. Some `Stmt`s may be contained
+  // in more than one `CFGBlock`; in this case, this function returns the
+  // innermost block (i.e. the one that is furthest from the root of the tree).
+  //
+  // The optional outparameter `Index` is set to the index into the block where
+  // the `Stmt` was found.
+  const CFGBlock *blockContainingStmt(const Stmt *S, size_t *Index = nullptr) const {
+    while (!Map.count(S)) {
+      SmallVector<const Stmt *, 1> Parents = getParentStmts(S, Context);
+      if (Parents.empty())
+        return nullptr;
+      S = Parents[0];
+    }
+
+    const auto &E = Map.lookup(S);
+    if (Index) *Index = E.second;
+    return E.first;
+  }
+
+private:
+  ASTContext *Context;
+
+  llvm::DenseMap<const Stmt *, std::pair<const CFGBlock *, size_t>> Map;
+};
+
+#endif // StmtToBlockMap_h__

build/clang-plugin/moz.build

@@ -16,6 +16,7 @@ UNIFIED_SOURCES += [
     'KungFuDeathGripChecker.cpp',
     'MozCheckAction.cpp',
     'MustOverrideChecker.cpp',
+    'MustReturnFromCallerChecker.cpp',
     'MustUseChecker.cpp',
     'NaNExprChecker.cpp',
     'NeedsNoVTableTypeChecker.cpp',

build/clang-plugin/plugin.h

@@ -5,6 +5,7 @@
 #ifndef plugin_h__
 #define plugin_h__
 
+#include "clang/Analysis/CFG.h"
 #include "clang/AST/ASTConsumer.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/RecursiveASTVisitor.h"

build/clang-plugin/tests/TestMustReturnFromCaller.cpp

@@ -0,0 +1,183 @@
+#include <cstddef>
+
+#define MOZ_MUST_RETURN_FROM_CALLER __attribute__((annotate("moz_must_return_from_caller")))
+#define MOZ_MAY_CALL_AFTER_MUST_RETURN __attribute__((annotate("moz_may_call_after_must_return")))
+
+void MOZ_MUST_RETURN_FROM_CALLER Throw() {}
+void DoAnythingElse();
+int MakeAnInt();
+int MOZ_MAY_CALL_AFTER_MUST_RETURN SafeMakeInt();
+bool Condition();
+
+class Foo {
+public:
+  __attribute__((annotate("moz_implicit"))) Foo(std::nullptr_t);
+  Foo();
+};
+
+void a1() {
+  Throw();
+}
+
+int a2() {
+  Throw(); // expected-error {{You must immediately return after calling this function}}
+  return MakeAnInt();
+}
+
+int a3() {
+  Throw();
+  return 5;
+}
+
+int a4() {
+  Throw(); // expected-error {{You must immediately return after calling this function}}
+  return Condition() ? MakeAnInt() : MakeAnInt();
+}
+
+void a5() {
+  Throw(); // expected-error {{You must immediately return after calling this function}}
+  DoAnythingElse();
+}
+
+int a6() {
+  Throw(); // expected-error {{You must immediately return after calling this function}}
+  DoAnythingElse();
+  return MakeAnInt();
+}
+
+int a7() {
+  Throw(); // expected-error {{You must immediately return after calling this function}}
+  DoAnythingElse();
+  return Condition() ? MakeAnInt() : MakeAnInt();
+}
+
+int a8() {
+  Throw();
+  return SafeMakeInt();
+}
+
+int a9() {
+  if (Condition()) {
+    Throw();
+  }
+  return SafeMakeInt();
+}
+
+void b1() {
+  if (Condition()) {
+    Throw();
+  }
+}
+
+int b2() {
+  if (Condition()) {
+    Throw(); // expected-error {{You must immediately return after calling this function}}
+  }
+  return MakeAnInt();
+}
+
+int b3() {
+  if (Condition()) {
+    Throw();
+  }
+  return 5;
+}
+
+int b4() {
+  if (Condition()) {
+    Throw(); // expected-error {{You must immediately return after calling this function}}
+  }
+  return Condition() ? MakeAnInt() : MakeAnInt();
+}
+
+void b5() {
+  if (Condition()) {
+    Throw(); // expected-error {{You must immediately return after calling this function}}
+  }
+  DoAnythingElse();
+}
+
+void b6() {
+  if (Condition()) {
+    Throw(); // expected-error {{You must immediately return after calling this function}}
+    DoAnythingElse();
+  }
+}
+
+void b7() {
+  if (Condition()) {
+    Throw();
+    return;
+  }
+  DoAnythingElse();
+}
+
+void b8() {
+  if (Condition()) {
+    Throw(); // expected-error {{You must immediately return after calling this function}}
+    DoAnythingElse();
+    return;
+  }
+  DoAnythingElse();
+}
+
+void b9() {
+  while (Condition()) {
+    Throw(); // expected-error {{You must immediately return after calling this function}}
+  }
+}
+
+void b10() {
+  while (Condition()) {
+    Throw();
+    return;
+  }
+}
+
+void b11() {
+  Throw(); // expected-error {{You must immediately return after calling this function}}
+  if (Condition()) {
+    return;
+  } else {
+    return;
+  }
+}
+
+void b12() {
+  switch (MakeAnInt()) {
+  case 1:
+    break;
+  default:
+    Throw();
+    return;
+  }
+}
+
+void b13() {
+  if (Condition()) {
+    Throw();
+  }
+  return;
+}
+
+Foo b14() {
+  if (Condition()) {
+    Throw();
+    return nullptr;
+  }
+  return nullptr;
+}
+
+Foo b15() {
+  if (Condition()) {
+    Throw();
+  }
+  return nullptr;
+}
+
+Foo b16() {
+  if (Condition()) {
+    Throw();
+  }
+  return Foo();
+}

build/clang-plugin/tests/moz.build

@@ -18,6 +18,7 @@ SOURCES += [
     'TestKungFuDeathGrip.cpp',
     'TestMultipleAnnotations.cpp',
     'TestMustOverride.cpp',
+    'TestMustReturnFromCaller.cpp',
     'TestMustUse.cpp',
     'TestNANTestingExpr.cpp',
     'TestNANTestingExprC.c',

caps/BasePrincipal.cpp

@@ -50,19 +50,6 @@ OriginAttributes::InitPrefs()
   }
 }
 
-void
-OriginAttributes::Inherit(const OriginAttributes& aAttrs)
-{
-  mAppId = aAttrs.mAppId;
-  mInIsolatedMozBrowser = aAttrs.mInIsolatedMozBrowser;
-
-
-  mUserContextId = aAttrs.mUserContextId;
-
-  mPrivateBrowsingId = aAttrs.mPrivateBrowsingId;
-  mFirstPartyDomain = aAttrs.mFirstPartyDomain;
-}
-
 void
 OriginAttributes::SetFirstPartyDomain(const bool aIsTopLevelDocument,
                                       nsIURI* aURI)

caps/BasePrincipal.h

@@ -40,10 +40,6 @@ public:
     : OriginAttributesDictionary(aOther)
   {}
 
-  // This method 'clones' the OriginAttributes ignoring the addonId value becaue
-  // this is computed from the principal URI and never propagated.
-  void Inherit(const OriginAttributes& aAttrs);
-
   void SetFirstPartyDomain(const bool aIsTopLevelDocument, nsIURI* aURI);
 
   enum {

caps/nsNullPrincipal.cpp

@@ -48,11 +48,9 @@ nsNullPrincipal::CreateWithInheritedAttributes(nsIPrincipal* aInheritFrom)
 /* static */ already_AddRefed<nsNullPrincipal>
 nsNullPrincipal::CreateWithInheritedAttributes(nsIDocShell* aDocShell)
 {
-  OriginAttributes attrs;
-  attrs.Inherit(nsDocShell::Cast(aDocShell)->GetOriginAttributes());
-
   RefPtr<nsNullPrincipal> nullPrin = new nsNullPrincipal();
-  nsresult rv = nullPrin->Init(attrs);
+  nsresult rv =
+    nullPrin->Init(nsDocShell::Cast(aDocShell)->GetOriginAttributes());
   MOZ_RELEASE_ASSERT(NS_SUCCEEDED(rv));
   return nullPrin.forget();
 }

caps/nsScriptSecurityManager.cpp

@@ -379,9 +379,11 @@ nsScriptSecurityManager::GetChannelURIPrincipal(nsIChannel* aChannel,
 
     // For addons loadInfo might be null.
     if (loadInfo) {
-      attrs.Inherit(loadInfo->GetOriginAttributes());
+      attrs = loadInfo->GetOriginAttributes();
     }
-    nsCOMPtr<nsIPrincipal> prin = BasePrincipal::CreateCodebasePrincipal(uri, attrs);
+
+    nsCOMPtr<nsIPrincipal> prin =
+      BasePrincipal::CreateCodebasePrincipal(uri, attrs);
     prin.forget(aPrincipal);
     return *aPrincipal ? NS_OK : NS_ERROR_FAILURE;
 }
@@ -1143,13 +1145,11 @@ nsScriptSecurityManager::
 {
   NS_ENSURE_STATE(aLoadContext);
   OriginAttributes docShellAttrs;
-  bool result = aLoadContext->GetOriginAttributes(docShellAttrs);;
+  bool result = aLoadContext->GetOriginAttributes(docShellAttrs);
   NS_ENSURE_TRUE(result, NS_ERROR_FAILURE);
 
-  OriginAttributes attrs;
-  attrs.Inherit(docShellAttrs);
-
-  nsCOMPtr<nsIPrincipal> prin = BasePrincipal::CreateCodebasePrincipal(aURI, attrs);
+  nsCOMPtr<nsIPrincipal> prin =
+    BasePrincipal::CreateCodebasePrincipal(aURI, docShellAttrs);
   prin.forget(aPrincipal);
   return *aPrincipal ? NS_OK : NS_ERROR_FAILURE;
 }
@@ -1159,10 +1159,8 @@ nsScriptSecurityManager::GetDocShellCodebasePrincipal(nsIURI* aURI,
                                                       nsIDocShell* aDocShell,
                                                       nsIPrincipal** aPrincipal)
 {
-  OriginAttributes attrs;
-  attrs.Inherit(nsDocShell::Cast(aDocShell)->GetOriginAttributes());
-
-  nsCOMPtr<nsIPrincipal> prin = BasePrincipal::CreateCodebasePrincipal(aURI, attrs);
+  nsCOMPtr<nsIPrincipal> prin =
+    BasePrincipal::CreateCodebasePrincipal(aURI, nsDocShell::Cast(aDocShell)->GetOriginAttributes());
   prin.forget(aPrincipal);
   return *aPrincipal ? NS_OK : NS_ERROR_FAILURE;
 }

devtools/client/debugger/new/debugger.js

@@ -36082,7 +36082,7 @@ return /******/ (function(modules) { // webpackBootstrap
 	
 	function removeChildren(e) {
 	  for (var count = e.childNodes.length; count > 0; --count)
-	    { e.removeChild(e.firstChild) }
+	    { e.firstChild.remove() }
 	  return e
 	}
 	

devtools/client/framework/sidebar.js

@@ -576,7 +576,7 @@ ToolSidebar.prototype = {
     }
 
     while (this._tabbox.tabs && this._tabbox.tabs.hasChildNodes()) {
-      this._tabbox.tabs.removeChild(this._tabbox.tabs.firstChild);
+      this._tabbox.tabs.firstChild.remove();
     }
 
     if (this._currentTool && this._telemetry) {

devtools/client/inspector/markup/markup.js

@@ -1604,7 +1604,7 @@ MarkupView.prototype = {
       // this container will do double duty as the container for the single
       // text child.
       while (container.children.firstChild) {
-        container.children.removeChild(container.children.firstChild);
+        container.children.firstChild.remove();
       }
 
       container.setInlineTextChild(container.node.inlineTextChild);
@@ -1616,7 +1616,7 @@ MarkupView.prototype = {
 
     if (!container.hasChildren) {
       while (container.children.firstChild) {
-        container.children.removeChild(container.children.firstChild);
+        container.children.firstChild.remove();
       }
       container.childrenDirty = false;
       container.setExpanded(false);
@@ -1659,7 +1659,7 @@ MarkupView.prototype = {
         }
 
         while (container.children.firstChild) {
-          container.children.removeChild(container.children.firstChild);
+          container.children.firstChild.remove();
         }
 
         if (!(children.hasFirst && children.hasLast)) {

devtools/client/inspector/markup/test/browser.ini

@@ -161,6 +161,7 @@ skip-if = e10s # Bug 1036409 - The last selected node isn't reselected
 [browser_markup_tag_edit_11.js]
 [browser_markup_tag_edit_12.js]
 [browser_markup_tag_edit_13-other.js]
+[browser_markup_tag_edit_avoid_refocus.js]
 [browser_markup_tag_edit_long-classname.js]
 [browser_markup_textcontent_display.js]
 [browser_markup_textcontent_edit_01.js]

devtools/client/inspector/markup/test/browser_markup_tag_edit_avoid_refocus.js

@@ -0,0 +1,43 @@
+/* vim: set ts=2 et sw=2 tw=80: */
+/* Any copyright is dedicated to the Public Domain.
+ http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Bug 1327683 - Tests that an editable attribute is not refocused
+// when the focus has been moved to an other element than the editor.
+
+const TEST_URL = 'data:text/html,<body class="abcd"></body>';
+
+add_task(function* () {
+  let {inspector} = yield openInspectorForURL(TEST_URL);
+
+  yield selectNode(".abcd", inspector);
+  yield clickContainer(".abcd", inspector);
+
+  let container = yield focusNode(".abcd", inspector);
+  ok(container && container.editor, "The markup-container was found");
+
+  info("Listening for the markupmutation event");
+  let nodeMutated = inspector.once("markupmutation");
+  let attr = container.editor.attrElements.get("class").querySelector(".editable");
+
+  attr.focus();
+  EventUtils.sendKey("return", inspector.panelWin);
+  let input = inplaceEditor(attr).input;
+  ok(input, "Found editable field for class attribute");
+
+  input.value = "class=\"wxyz\"";
+
+  let onFocus = once(inspector.searchBox, "focus");
+  EventUtils.synthesizeMouseAtCenter(inspector.searchBox, {}, inspector.panelWin);
+
+  info("Wait for the focus event on search box");
+  yield onFocus;
+
+  info("Wait for the markup-mutation event");
+  yield nodeMutated;
+
+  is(inspector.panelDoc.activeElement, inspector.searchBox,
+     "The currently focused element is the search box");
+});

devtools/client/inspector/markup/views/element-editor.js

@@ -447,6 +447,13 @@ ElementEditor.prototype = {
       this._editedAttributeObserver = null;
     }
 
+    let activeElement = this.markup.doc.activeElement;
+    if (!activeElement || !activeElement.inplaceEditor) {
+      // The focus was already removed from the current inplace editor, we should not
+      // refocus the editable attribute.
+      return;
+    }
+
     let container = this.markup.getContainer(this.node);
 
     let activeAttrs = [...this.attrList.childNodes]

devtools/client/scratchpad/scratchpad.js

@@ -1367,7 +1367,7 @@ var Scratchpad = {
 
     recentFilesMenu.setAttribute("disabled", true);
     while (recentFilesPopup.hasChildNodes()) {
-      recentFilesPopup.removeChild(recentFilesPopup.firstChild);
+      recentFilesPopup.firstChild.remove();
     }
 
     if (filePaths.length > 0) {

devtools/client/shared/developer-toolbar.js

@@ -1019,7 +1019,7 @@ OutputPanel.prototype._update = function () {
 
   // Empty this._div
   while (this._div.hasChildNodes()) {
-    this._div.removeChild(this._div.firstChild);
+    this._div.firstChild.remove();
   }
 
   if (this.displayedOutput.data != null) {
@@ -1030,7 +1030,7 @@ OutputPanel.prototype._update = function () {
       }
 
       while (this._div.hasChildNodes()) {
-        this._div.removeChild(this._div.firstChild);
+        this._div.firstChild.remove();
       }
 
       let links = node.querySelectorAll("*[href]");

devtools/client/shared/widgets/TableWidget.js

@@ -1554,7 +1554,7 @@ Cell.prototype = {
       this.label.removeAttribute("value");
 
       while (this.label.firstChild) {
-        this.label.removeChild(this.label.firstChild);
+        this.label.firstChild.remove();
       }
 
       this.label.appendChild(value);

devtools/client/shared/widgets/tooltip/Tooltip.js

@@ -201,7 +201,7 @@ Tooltip.prototype = {
    */
   empty: function () {
     while (this.panel.hasChildNodes()) {
-      this.panel.removeChild(this.panel.firstChild);
+      this.panel.firstChild.remove();
     }
   },
 

devtools/client/styleeditor/StyleEditorUI.jsm

@@ -865,7 +865,7 @@ StyleEditorUI.prototype = {
       let list = details.querySelector(".stylesheet-media-list");
 
       while (list.firstChild) {
-        list.removeChild(list.firstChild);
+        list.firstChild.remove();
       }
 
       let rules = editor.mediaRules;

devtools/shared/gcli/commands/csscoverage.js

@@ -156,7 +156,7 @@ exports.items = [
         onback: () => {
           // The back button clears and hides .csscoverage-report
           while (host.hasChildNodes()) {
-            host.removeChild(host.firstChild);
+            host.firstChild.remove();
           }
           host.hidden = true;
         }

devtools/shared/gcli/source/lib/gcli/util/util.js

@@ -388,7 +388,7 @@ exports.createElement = function(doc, tag) {
  */
 exports.clearElement = function(elem) {
   while (elem.hasChildNodes()) {
-    elem.removeChild(elem.firstChild);
+    elem.firstChild.remove();
   }
 };
 

docshell/base/LoadContext.cpp

@@ -51,7 +51,7 @@ LoadContext::LoadContext(nsIPrincipal* aPrincipal,
   , mIsNotNull(true)
 #endif
 {
-  mOriginAttributes.Inherit(aPrincipal->OriginAttributesRef());
+  mOriginAttributes = aPrincipal->OriginAttributesRef();
   if (!aOptionalBase) {
     return;
   }

docshell/base/nsDocShell.cpp

@@ -5003,8 +5003,6 @@ nsDocShell::DisplayLoadError(nsresult aError, nsIURI* aURI,
         // 12.1, HPKP draft spec section 2.6).
         uint32_t flags =
           UsePrivateBrowsing() ? nsISocketProvider::NO_PERMANENT_STORAGE : 0;
-        OriginAttributes originAttributes;
-        originAttributes.Inherit(mOriginAttributes);
         bool isStsHost = false;
         bool isPinnedHost = false;
         if (XRE_IsParentProcess()) {
@@ -5012,10 +5010,10 @@ nsDocShell::DisplayLoadError(nsresult aError, nsIURI* aURI,
             do_GetService(NS_SSSERVICE_CONTRACTID, &rv);
           NS_ENSURE_SUCCESS(rv, rv);
           rv = sss->IsSecureURI(nsISiteSecurityService::HEADER_HSTS, aURI,
-                                flags, originAttributes, nullptr, &isStsHost);
+                                flags, mOriginAttributes, nullptr, &isStsHost);
           NS_ENSURE_SUCCESS(rv, rv);
           rv = sss->IsSecureURI(nsISiteSecurityService::HEADER_HPKP, aURI,
-                                flags, originAttributes, nullptr,
+                                flags, mOriginAttributes, nullptr,
                                 &isPinnedHost);
           NS_ENSURE_SUCCESS(rv, rv);
         } else {
@@ -5024,9 +5022,9 @@ nsDocShell::DisplayLoadError(nsresult aError, nsIURI* aURI,
           mozilla::ipc::URIParams uri;
           SerializeURI(aURI, uri);
           cc->SendIsSecureURI(nsISiteSecurityService::HEADER_HSTS, uri, flags,
-                              originAttributes, &isStsHost);
+                              mOriginAttributes, &isStsHost);
           cc->SendIsSecureURI(nsISiteSecurityService::HEADER_HPKP, uri, flags,
-                              originAttributes, &isPinnedHost);
+                              mOriginAttributes, &isPinnedHost);
         }
 
         if (Preferences::GetBool(
@@ -9736,10 +9734,8 @@ nsresult
 nsDocShell::CreatePrincipalFromReferrer(nsIURI* aReferrer,
                                         nsIPrincipal** aResult)
 {
-  OriginAttributes attrs;
-  attrs.Inherit(mOriginAttributes);
   nsCOMPtr<nsIPrincipal> prin =
-    BasePrincipal::CreateCodebasePrincipal(aReferrer, attrs);
+    BasePrincipal::CreateCodebasePrincipal(aReferrer, mOriginAttributes);
   prin.forget(aResult);
 
   return *aResult ? NS_OK : NS_ERROR_FAILURE;
@@ -10729,11 +10725,11 @@ nsDocShell::InternalLoad(nsIURI* aURI,
     srcdoc = NullString();
   }
 
-  OriginAttributes attrs;
   bool isTopLevelDoc = mItemType == typeContent &&
                        (isTargetTopLevelDocShell ||
                         GetIsMozBrowser());
-  attrs.Inherit(GetOriginAttributes());
+
+  OriginAttributes attrs = GetOriginAttributes();
   attrs.SetFirstPartyDomain(isTopLevelDoc, aURI);
 
   net::PredictorLearn(aURI, nullptr,
@@ -10985,9 +10981,9 @@ nsDocShell::DoURILoad(nsIURI* aURI,
                        (aContentPolicyType == nsIContentPolicy::TYPE_DOCUMENT ||
                         GetIsMozBrowser());
 
-  OriginAttributes attrs;
-  attrs.Inherit(GetOriginAttributes());
+  OriginAttributes attrs = GetOriginAttributes();
   attrs.SetFirstPartyDomain(isTopLevelDoc, aURI);
+
   rv = loadInfo->SetOriginAttributes(attrs);
   if (NS_WARN_IF(NS_FAILED(rv))) {
     return rv;
@@ -12602,9 +12598,6 @@ nsDocShell::LoadHistoryEntry(nsISHEntry* aEntry, uint32_t aLoadType)
     srcdoc = NullString();
   }
 
-  // If there is no valid triggeringPrincipal, we deny the load
-  MOZ_ASSERT(triggeringPrincipal,
-             "need a valid triggeringPrincipal to load from history");
   if (!triggeringPrincipal) {
     triggeringPrincipal = nsContentUtils::GetSystemPrincipal();
   }
@@ -14231,12 +14224,10 @@ nsDocShell::OnOverLink(nsIContent* aContent,
   rv = textToSubURI->UnEscapeURIForUI(charset, spec, uStr);
   NS_ENSURE_SUCCESS(rv, rv);
 
-  OriginAttributes attrs;
-  attrs.Inherit(aContent->NodePrincipal()->OriginAttributesRef());
-
   mozilla::net::PredictorPredict(aURI, mCurrentURI,
                                  nsINetworkPredictor::PREDICT_LINK,
-                                 attrs, nullptr);
+                                 aContent->NodePrincipal()->OriginAttributesRef(),
+                                 nullptr);
 
   if (browserChrome2) {
     nsCOMPtr<nsIDOMElement> element = do_QueryInterface(aContent);
@@ -14748,10 +14739,8 @@ nsDocShell::ShouldPrepareForIntercept(nsIURI* aURI, bool aIsNonSubresourceReques
   }
 
   if (aIsNonSubresourceRequest) {
-    OriginAttributes attrs;
-    attrs.Inherit(mOriginAttributes);
     nsCOMPtr<nsIPrincipal> principal =
-      BasePrincipal::CreateCodebasePrincipal(aURI, attrs);
+      BasePrincipal::CreateCodebasePrincipal(aURI, mOriginAttributes);
     *aShouldIntercept = swm->IsAvailable(principal, aURI);
     return NS_OK;
   }
@@ -14800,12 +14789,9 @@ nsDocShell::ChannelIntercepted(nsIInterceptedChannel* aChannel)
 
   bool isReload = mLoadType & LOAD_CMD_RELOAD;
 
-  OriginAttributes attrs;
-  attrs.Inherit(mOriginAttributes);
-
   ErrorResult error;
-  swm->DispatchFetchEvent(attrs, doc, mInterceptedDocumentId, aChannel,
-                          isReload, isSubresourceLoad, error);
+  swm->DispatchFetchEvent(mOriginAttributes, doc, mInterceptedDocumentId,
+                          aChannel, isReload, isSubresourceLoad, error);
   if (NS_WARN_IF(error.Failed())) {
     return error.StealNSResult();
   }

docshell/shistory/nsSHEntry.cpp

@@ -513,10 +513,6 @@ nsSHEntry::GetTriggeringPrincipal(nsIPrincipal** aTriggeringPrincipal)
 NS_IMETHODIMP
 nsSHEntry::SetTriggeringPrincipal(nsIPrincipal* aTriggeringPrincipal)
 {
-  MOZ_ASSERT(aTriggeringPrincipal, "need a valid triggeringPrincipal");
-  if (!aTriggeringPrincipal) {
-    return NS_ERROR_FAILURE;
-  }
   mShared->mTriggeringPrincipal = aTriggeringPrincipal;
   return NS_OK;
 }

docshell/test/chrome/bug303267.html

@@ -13,7 +13,7 @@ function showpageshowcount()
 	var div1 = document.getElementById("div1");
 	while (div1.firstChild)
 	{
-		div1.removeChild(div1.firstChild);
+		div1.firstChild.remove();
 	}
 	div1.appendChild(document.createTextNode(
 	  "pageshowcount: " + pageshowcount));

docshell/test/navigation/file_bug534178.html

@@ -3,7 +3,7 @@
     <script>
     
       function testDone() {
-        document.body.removeChild(document.body.firstChild);
+        document.body.firstChild.remove();
         var isOK = false;
         try {
           isOK = history.previous != location;

docshell/test/test_bug570341.html

@@ -31,7 +31,7 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=570341
 
   function showSequence(node){
     while(node.firstChild) {
-      node.removeChild(node.firstChild);
+      node.firstChild.remove();
     }
     var sequence = [];
     for (var p in moments) {

dom/animation/Animation.cpp

@@ -416,7 +416,9 @@ Animation::GetReady(ErrorResult& aRv)
   }
   if (!mReady) {
     aRv.Throw(NS_ERROR_FAILURE);
-  } else if (PlayState() != AnimationPlayState::Pending) {
+    return nullptr;
+  }
+  if (PlayState() != AnimationPlayState::Pending) {
     mReady->MaybeResolve(this);
   }
   return mReady;
@@ -431,7 +433,9 @@ Animation::GetFinished(ErrorResult& aRv)
   }
   if (!mFinished) {
     aRv.Throw(NS_ERROR_FAILURE);
-  } else if (mFinishedIsResolved) {
+    return nullptr;
+  }
+  if (mFinishedIsResolved) {
     MaybeResolveFinishedPromise();
   }
   return mFinished;

dom/animation/KeyframeUtils.cpp

@@ -473,8 +473,8 @@ KeyframeUtils::GetKeyframesFromObject(JSContext* aCx,
   if ((!AnimationUtils::IsCoreAPIEnabled() ||
        aDocument->IsStyledByServo()) &&
       RequiresAdditiveAnimation(keyframes, aDocument)) {
-    aRv.Throw(NS_ERROR_DOM_ANIM_MISSING_PROPS_ERR);
     keyframes.Clear();
+    aRv.Throw(NS_ERROR_DOM_ANIM_MISSING_PROPS_ERR);
   }
 
   return keyframes;
@@ -770,8 +770,8 @@ GetKeyframeListFromKeyframeSequence(JSContext* aCx,
   // Convert the object in aIterator to a sequence of keyframes producing
   // an array of Keyframe objects.
   if (!ConvertKeyframeSequence(aCx, aDocument, aIterator, aResult)) {
-    aRv.Throw(NS_ERROR_FAILURE);
     aResult.Clear();
+    aRv.Throw(NS_ERROR_FAILURE);
     return;
   }
 

dom/base/StructuredCloneHolder.cpp

@@ -302,6 +302,7 @@ StructuredCloneHolder::Read(nsISupports* aParent,
   if (!StructuredCloneHolderBase::Read(aCx, aValue)) {
     JS_ClearPendingException(aCx);
     aRv.Throw(NS_ERROR_DOM_DATA_CLONE_ERR);
+    return;
   }
 
   // If we are tranferring something, we cannot call 'Read()' more than once.

dom/base/TextInputProcessor.cpp

@@ -698,6 +698,13 @@ TextInputProcessor::NotifyIME(TextEventDispatcher* aTextEventDispatcher,
   }
 }
 
+NS_IMETHODIMP_(nsIMEUpdatePreference)
+TextInputProcessor::GetIMEUpdatePreference()
+{
+  // TextInputProcessor::NotifyIME does not require extra change notifications.
+  return nsIMEUpdatePreference();
+}
+
 NS_IMETHODIMP_(void)
 TextInputProcessor::OnRemovedFrom(TextEventDispatcher* aTextEventDispatcher)
 {

dom/base/TextInputProcessor.h

@@ -32,6 +32,9 @@ public:
   // TextEventDispatcherListener
   NS_IMETHOD NotifyIME(TextEventDispatcher* aTextEventDispatcher,
                        const IMENotification& aNotification) override;
+
+  NS_IMETHOD_(nsIMEUpdatePreference) GetIMEUpdatePreference() override;
+
   NS_IMETHOD_(void)
     OnRemovedFrom(TextEventDispatcher* aTextEventDispatcher) override;
 

dom/base/crashtests/771639.html

@@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <script>
 var root = document.documentElement;
-while(root.firstChild) { root.removeChild(root.firstChild); }
+while(root.firstChild) { root.firstChild.remove(); }
 var div = document.createElement("div");
 root.appendChild(div);
 

dom/base/nsDOMAttributeMap.cpp

@@ -319,8 +319,9 @@ nsDOMAttributeMap::SetNamedItemNS(Attr& aAttr, ErrorResult& aError)
   rv = mContent->SetAttr(ni->NamespaceID(), ni->NameAtom(),
                          ni->GetPrefixAtom(), value, true);
   if (NS_FAILED(rv)) {
-    aError.Throw(rv);
     DropAttribute(ni->NamespaceID(), ni->NameAtom());
+    aError.Throw(rv);
+    return nullptr;
   }
 
   return oldAttr.forget();

dom/base/nsFrameLoader.cpp

@@ -2452,7 +2452,7 @@ nsFrameLoader::MaybeCreateDocShell()
     MOZ_ASSERT(attrs.mPrivateBrowsingId == oa.mPrivateBrowsingId,
               "docshell and document should have the same privateBrowsingId attribute.");
 
-    attrs.Inherit(oa);
+    attrs = oa;
   }
 
   if (OwnerIsMozBrowserFrame()) {

dom/base/nsGlobalWindow.cpp

@@ -3267,7 +3267,11 @@ nsGlobalWindow::DispatchDOMWindowCreated()
 
   nsCOMPtr<nsIObserverService> observerService =
     mozilla::services::GetObserverService();
-  if (observerService) {
+
+  // The event dispatching could possibly cause docshell destory, and
+  // consequently cause mDoc to be set to nullptr by DropOuterWindowDocs(),
+  // so check it again here.
+  if (observerService && mDoc) {
     nsAutoString origin;
     nsIPrincipal* principal = mDoc->NodePrincipal();
     nsContentUtils::GetUTFOrigin(principal, origin);

dom/base/nsScriptLoader.cpp

@@ -1313,11 +1313,9 @@ nsScriptLoader::StartLoad(nsScriptLoadRequest *aRequest)
     }
   }
 
-  OriginAttributes attrs;
-  attrs.Inherit(mDocument->NodePrincipal()->OriginAttributesRef());
-
   mozilla::net::PredictorLearn(aRequest->mURI, mDocument->GetDocumentURI(),
-      nsINetworkPredictor::LEARN_LOAD_SUBRESOURCE, attrs);
+                               nsINetworkPredictor::LEARN_LOAD_SUBRESOURCE,
+                               mDocument->NodePrincipal()->OriginAttributesRef());
 
   // Set the initiator type
   nsCOMPtr<nsITimedChannel> timedChannel(do_QueryInterface(httpChannel));

dom/base/test/chrome/chrome.ini

@@ -72,3 +72,4 @@ support-files = ../file_bug357450.js
 [test_windowroot.xul]
 [test_swapFrameLoaders.xul]
 [test_groupedSHistory.xul]
+[test_bug1339722.html]

dom/base/test/chrome/test_bug1339722.html

@@ -0,0 +1,67 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1339722
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Test for Bug 1339722</title>
+  <script type="application/javascript" src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="chrome://global/skin"/>
+  <link rel="stylesheet" type="text/css" href="chrome://mochikit/content/tests/SimpleTest/test.css"/>
+  <script type="application/javascript">
+
+  /**
+   * Test for Bug 1339722
+   * 1. Wait for "http-on-useragent-request" for the iframe load.
+   * 2. In the observer, access it's window proxy to trigger DOMWindowCreated.
+   * 3. In the event handler, delete the iframe so that the frameloader would be
+   *    destoryed in the middle of ReallyStartLoading.
+   * 4. Verify that it doesn't crash.
+  **/
+
+  const {interfaces: Ci, utils: Cu} = Components;
+  Cu.import("resource://gre/modules/Services.jsm");
+
+  const TOPIC = 'http-on-useragent-request';
+  Services.obs.addObserver({
+    observe(subject, topic, data) {
+      info('Got ' + topic);
+      Services.obs.removeObserver(this, TOPIC);
+
+      // Query window proxy so it triggers DOMWindowCreated.
+      let channel = subject.QueryInterface(Ci.nsIHttpChannel);
+      let win = channel.notificationCallbacks.getInterface(Ci.mozIDOMWindowProxy);
+    }
+  }, TOPIC, false);
+
+  let docShell = SpecialPowers.wrap(window)
+                              .QueryInterface(Ci.nsIInterfaceRequestor)
+                              .getInterface(Ci.nsIDocShell);
+  docShell.chromeEventHandler.addEventListener('DOMWindowCreated', function handler(e) {
+    docShell.chromeEventHandler.removeEventListener('DOMWindowCreated', handler);
+    let iframe = document.getElementById('testFrame');
+    is(e.target, iframe.contentDocument, 'verify event target');
+
+    // Remove the iframe to cause frameloader destroy.
+    iframe.remove();
+    setTimeout($ => {
+      ok(!document.getElementById('testFrame'), 'verify iframe removed');
+      SimpleTest.finish();
+    }, 0);
+  });
+
+  SimpleTest.waitForExplicitFinish();
+  </script>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1339722">Mozilla Bug 1339722</a>
+<p id="display"></p>
+<div id="content" style="display: none"></div>
+<pre id="test">
+  <div id="frameContainer">
+    <iframe id="testFrame" src="http://www.example.com"></iframe>
+  </div>
+</pre>
+</body>
+</html>

dom/base/test/test_bug416383.html

@@ -26,7 +26,7 @@ function runTest() {
   ok(attrs != null, "Element should have attributes!");
   var attr = testParent.firstChild.getAttributeNode("someattr");
   ok(attr.value == "foo", "The value of the attribute should be 'foo'!");
-  testParent.removeChild(testParent.firstChild);
+  testParent.firstChild.remove();
   SpecialPowers.gc();
   ok(true, "Browser should not crash!")
 

dom/base/test/test_mutationobservers.html

@@ -246,7 +246,7 @@ function testChildList() {
       m = null;
     });
   m.observe(div, { childList: true});
-  div.removeChild(div.firstChild);
+  div.firstChild.remove();
 }
 
 function testChildList2() {

dom/bindings/CallbackObject.cpp

@@ -334,7 +334,7 @@ CallbackObject::CallSetup::~CallSetup()
 
         // IsJSContextException shouldn't be true anymore because we will report
         // the exception on the JSContext ... so throw something else.
-        mErrorResult.Throw(NS_ERROR_UNEXPECTED);
+        mErrorResult.ThrowWithCustomCleanup(NS_ERROR_UNEXPECTED);
       }
     }
   }

dom/bindings/Codegen.py

@@ -5468,7 +5468,7 @@ def getJSToNativeConversionInfo(type, descriptorProvider, failureCode=None,
               nsCOMPtr<nsIGlobalObject> global =
                 do_QueryInterface(promiseGlobal.GetAsSupports());
               if (!global) {
-                promiseRv.Throw(NS_ERROR_UNEXPECTED);
+                promiseRv.ThrowWithCustomCleanup(NS_ERROR_UNEXPECTED);
                 promiseRv.MaybeSetPendingException(cx);
                 $*{exceptionCode}
               }

dom/bindings/ErrorResult.h

@@ -165,11 +165,48 @@ public:
   operator ErrorResult&();
   operator OOMReporter&();
 
-  void Throw(nsresult rv) {
+  void MOZ_MUST_RETURN_FROM_CALLER Throw(nsresult rv) {
     MOZ_ASSERT(NS_FAILED(rv), "Please don't try throwing success");
     AssignErrorCode(rv);
   }
 
+  // This method acts identically to the `Throw` method, however, it does not
+  // have the MOZ_MUST_RETURN_FROM_CALLER static analysis annotation. It is
+  // intended to be used in situations when additional work needs to be
+  // performed in the calling function after the Throw method is called.
+  //
+  // In general you should prefer using `Throw`, and returning after an error,
+  // for example:
+  //
+  //   if (condition) {
+  //     aRv.Throw(NS_ERROR_FAILURE);
+  //     return;
+  //   }
+  //
+  // or
+  //
+  //   if (condition) {
+  //     aRv.Throw(NS_ERROR_FAILURE);
+  //   }
+  //   return;
+  //
+  // However, if you need to do some other work after throwing, such as:
+  //
+  //   if (condition) {
+  //     aRv.ThrowWithCustomCleanup(NS_ERROR_FAILURE);
+  //   }
+  //   // Do some important clean-up work which couldn't happen earlier.
+  //   // We want to do this clean-up work in both the success and failure cases.
+  //   CleanUpImportantState();
+  //   return;
+  //
+  // Then you'll need to use ThrowWithCustomCleanup to get around the static
+  // analysis, which would complain that you are doing work after the call to
+  // `Throw()`.
+  void ThrowWithCustomCleanup(nsresult rv) {
+    Throw(rv);
+  }
+
   // Duplicate our current state on the given TErrorResult object.  Any
   // existing errors or messages on the target will be suppressed before
   // cloning.  Our own error state remains unchanged.
@@ -307,7 +344,7 @@ public:
   }
 
   // Support for uncatchable exceptions.
-  void ThrowUncatchableException() {
+  void MOZ_MUST_RETURN_FROM_CALLER ThrowUncatchableException() {
     Throw(NS_ERROR_UNCATCHABLE_EXCEPTION);
   }
   bool IsUncatchableException() const {

dom/canvas/ImageBitmap.cpp

@@ -1482,6 +1482,7 @@ ImageBitmap::Create(nsIGlobalObject* aGlobal, const ImageBitmapSource& aSrc,
     return promise.forget();
   } else {
     aRv.Throw(NS_ERROR_NOT_IMPLEMENTED);
+    return nullptr;
   }
 
   if (!aRv.Failed()) {
@@ -1691,13 +1692,13 @@ protected:
     } else if (JS_IsArrayBufferViewObject(mBuffer)) {
       js::GetArrayBufferViewLengthAndData(mBuffer, &bufferLength, &isSharedMemory, &bufferData);
     } else {
-      error.Throw(NS_ERROR_NOT_IMPLEMENTED);
+      error.ThrowWithCustomCleanup(NS_ERROR_NOT_IMPLEMENTED);
       mPromise->MaybeReject(error);
       return;
     }
 
     if (NS_WARN_IF(!bufferData) || NS_WARN_IF(!bufferLength)) {
-      error.Throw(NS_ERROR_NOT_AVAILABLE);
+      error.ThrowWithCustomCleanup(NS_ERROR_NOT_AVAILABLE);
       mPromise->MaybeReject(error);
       return;
     }
@@ -1707,7 +1708,7 @@ protected:
       mImageBitmap->MappedDataLength(mFormat, error);
 
     if (((int32_t)bufferLength - mOffset) < neededBufferLength) {
-      error.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);
+      error.ThrowWithCustomCleanup(NS_ERROR_DOM_INDEX_SIZE_ERR);
       mPromise->MaybeReject(error);
       return;
     }

dom/canvas/WebGLContextVertices.cpp

@@ -250,9 +250,11 @@ WebGLContext::GetVertexAttrib(JSContext* cx, GLuint index, GLenum pname,
                 break;
             }
 
-            if (!obj)
+            if (!obj) {
                 rv.Throw(NS_ERROR_OUT_OF_MEMORY);
-            return JS::ObjectOrNullValue(obj);
+                return JS::NullValue();
+            }
+            return JS::ObjectValue(*obj);
         }
 
     case LOCAL_GL_VERTEX_ATTRIB_ARRAY_ENABLED:

dom/encoding/TextEncoder.cpp

@@ -67,6 +67,7 @@ TextEncoder::Encode(JSContext* aCx,
 
   if (NS_FAILED(rv)) {
     aRv.Throw(rv);
+    return;
   }
   aRetval.set(outView);
 }

dom/events/DataTransfer.cpp

@@ -332,8 +332,11 @@ DataTransfer::GetTypes(nsTArray<nsString>& aTypes, CallerType aCallerType) const
       continue;
     }
 
+    // NOTE: The reason why we get the internal type here is because we want
+    // kFileMime to appear in the types list for backwards compatibility
+    // reasons.
     nsAutoString type;
-    item->GetType(type);
+    item->GetInternalType(type);
     if (item->Kind() == DataTransferItem::KIND_STRING || type.EqualsASCII(kFileMime)) {
       // If the entry has kind KIND_STRING, we want to add it to the list.
       aTypes.AppendElement(type);
@@ -521,8 +524,11 @@ DataTransfer::MozTypesAt(uint32_t aIndex, CallerType aCallerType,
         continue;
       }
 
+      // NOTE: The reason why we get the internal type here is because we want
+      // kFileMime to appear in the types list for backwards compatibility
+      // reasons.
       nsAutoString type;
-      items[i]->GetType(type);
+      items[i]->GetInternalType(type);
       if (NS_WARN_IF(!types->Add(type))) {
         aRv.Throw(NS_ERROR_FAILURE);
         return nullptr;
@@ -981,7 +987,7 @@ DataTransfer::GetTransferable(uint32_t aIndex, nsILoadContext* aLoadContext)
       }
 
       nsAutoString type;
-      formatitem->GetType(type);
+      formatitem->GetInternalType(type);
 
       // If the data is of one of the well-known formats, use it directly.
       bool isCustomFormat = true;

dom/events/DataTransferItem.cpp

@@ -230,6 +230,37 @@ DataTransferItem::FillInExternalData()
   }
 }
 
+void
+DataTransferItem::GetType(nsAString& aType)
+{
+  // If we don't have a File, we can just put whatever our recorded internal
+  // type is.
+  if (Kind() != KIND_FILE) {
+    aType = mType;
+    return;
+  }
+
+  // If we do have a File, then we need to look at our File object to discover
+  // what its mime type is. We can use the System Principal here, as this
+  // information should be avaliable even if the data is currently inaccessible
+  // (for example during a dragover).
+  //
+  // XXX: This seems inefficient, as it seems like we should be able to get this
+  // data without getting the entire File object, which may require talking to
+  // the OS.
+  ErrorResult rv;
+  RefPtr<File> file = GetAsFile(*nsContentUtils::GetSystemPrincipal(), rv);
+  MOZ_ASSERT(!rv.Failed(), "Failed to get file data with system principal");
+
+  // If we don't actually have a file, fall back to returning the internal type.
+  if (NS_WARN_IF(!file)) {
+    aType = mType;
+    return;
+  }
+
+  file->GetType(aType);
+}
+
 already_AddRefed<File>
 DataTransferItem::GetAsFile(nsIPrincipal& aSubjectPrincipal,
                             ErrorResult& aRv)

dom/events/DataTransferItem.h

@@ -69,11 +69,13 @@ public:
     }
   }
 
-  void GetType(nsAString& aType) const
+  void GetInternalType(nsAString& aType) const
   {
     aType = mType;
   }
 
+  void GetType(nsAString& aType);
+
   eKind Kind() const
   {
     return mKind;

dom/events/DataTransferItemList.cpp

@@ -294,8 +294,9 @@ DataTransferItemList::MozRemoveByTypeAt(const nsAString& aType,
   }
 
   for (uint32_t i = 0; i < count; ++i) {
+    // NOTE: As this is a moz-prefixed API, it works based on internal types.
     nsAutoString type;
-    items[i]->GetType(type);
+    items[i]->GetInternalType(type);
     if (type == aType) {
       ClearDataHelper(items[i], -1, i, aSubjectPrincipal, aRv);
       return;
@@ -313,8 +314,9 @@ DataTransferItemList::MozItemByTypeAt(const nsAString& aType, uint32_t aIndex)
   uint32_t count = mIndexedItems[aIndex].Length();
   for (uint32_t i = 0; i < count; i++) {
     RefPtr<DataTransferItem> item = mIndexedItems[aIndex][i];
+    // NOTE: As this is a moz-prefixed API it works on internal types
     nsString type;
-    item->GetType(type);
+    item->GetInternalType(type);
     if (type.Equals(aType)) {
       return item;
     }
@@ -338,7 +340,7 @@ DataTransferItemList::SetDataWithPrincipal(const nsAString& aType,
     for (uint32_t i = 0; i < count; i++) {
       RefPtr<DataTransferItem> item = items[i];
       nsString type;
-      item->GetType(type);
+      item->GetInternalType(type);
       if (type.Equals(aType)) {
         if (NS_WARN_IF(aInsertOnly)) {
           aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);

dom/events/test/test_DataTransferItemList.html

@@ -98,7 +98,7 @@
       is(oldLength + 1, dtList.length,
          "Replacing the entry with a file should add it to the list!");
       is(dtList[oldLength].getAsFile(), file3, "It should be stored in the last index as a file");
-      is(dtList[oldLength].type, "random/string", "It should have the correct type");
+      is(dtList[oldLength].type, "text/html", "It should have the correct type");
       is(dtList[oldLength].kind, "file", "It should have the correct kind");
 
       todo(files.length == 3, "This test has chrome privileges, so the FileList objects aren't updated live");

dom/filesystem/GetFilesTask.cpp

@@ -202,8 +202,8 @@ GetFilesTaskParent::GetSuccessRequestResult(ErrorResult& aRv) const
 
   FallibleTArray<FileSystemFileResponse> inputs;
   if (!inputs.SetLength(mTargetBlobImplArray.Length(), mozilla::fallible_t())) {
-    aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
     FileSystemFilesResponse response;
+    aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
     return response;
   }
 

dom/flyweb/FlyWebService.cpp

@@ -1193,7 +1193,7 @@ FlyWebService::PairWithService(const nsAString& aServiceId,
 
   if (NS_FAILED(rv)) {
     ErrorResult result;
-    result.Throw(rv);
+    result.ThrowWithCustomCleanup(rv);
     const nsAString& reason = NS_LITERAL_STRING("Error pairing.");
     aCallback.PairingFailed(reason, result);
     ENSURE_SUCCESS_VOID(result);

dom/flyweb/HttpServer.cpp

@@ -192,9 +192,8 @@ HttpServer::AcceptWebSocket(InternalRequest* aConnectRequest,
     return provider.forget();
   }
 
-  aRv.Throw(NS_ERROR_UNEXPECTED);
   MOZ_ASSERT(false, "Unknown request");
-
+  aRv.Throw(NS_ERROR_UNEXPECTED);
   return nullptr;
 }
 

dom/html/HTMLMediaElement.cpp

@@ -2701,6 +2701,7 @@ HTMLMediaElement::Seek(double aTime,
   nsresult rv = mDecoder->Seek(aTime, aSeekType, promise);
   if (NS_FAILED(rv)) {
     aRv.Throw(rv);
+    return nullptr;
   }
 
   // We changed whether we're seeking so we need to AddRemoveSelfReference.

dom/html/crashtests/453406-1.html

@@ -5,7 +5,7 @@ function boom()
 {
   var r = document.documentElement;
   while (r.firstChild)
-    r.removeChild(r.firstChild);
+    r.firstChild.remove();
 
   var b    = document.createElement("BODY");
   var s    = document.createElement("SCRIPT");

dom/html/crashtests/564461.xhtml

@@ -11,7 +11,7 @@
 
 function boom()
 {
-  while (document.documentElement.firstChild) document.documentElement.removeChild(document.documentElement.firstChild);
+  while (document.documentElement.firstChild) document.documentElement.firstChild.remove();
   
   document.addEventListener("DOMSubtreeModified", function(){});
   document.addEventListener("DOMNodeInsertedIntoDocument", function(){});

dom/html/test/forms/test_form_attribute-1.html

@@ -424,7 +424,7 @@ for (var name of elementNames) {
   for (var func of functions) {
     // Clean-up.
     while (content.firstChild) {
-      content.removeChild(content.firstChild);
+      content.firstChild.remove();
     }
     for (form of forms) {
       content.appendChild(form);

dom/html/test/test_bug300691-1.html

@@ -95,7 +95,7 @@ valueIs("abcdeTesth",
         "Modifying textnode text shouldn't affect value in edited textarea");
 defValueIs("abcdefghlmno", "Modified textnode text 3");
 
-t.removeChild(t.firstChild);
+t.firstChild.remove();
 valueIs("abcdeTesth",
         "Removing child textnode shouldn't affect value in edited textarea");
 defValueIs("defghlmno", "Removed textnode 3");

dom/html/test/test_bug311681.html

@@ -78,7 +78,7 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=311681
 
   function clear(node) {
     while (node.hasChildNodes()) {
-      node.removeChild(node.firstChild);
+      node.firstChild.remove();
     }
   }