Bug 1500180 - Take around only geometry data of the fallback tab for pended operations. r=mixedpuppy

browser/components/extensions/parent/ext-browser.js

@@ -444,16 +444,21 @@ class TabTracker extends TabTrackerBase {
             windowId: windowTracker.getId(nativeTab.ownerGlobal),
           });
         } else {
-          // Save the current tab, since the newly-created tab will likely be
-          // active by the time the promise below resolves and the event is
-          // dispatched.
-          let currentTab = nativeTab.ownerGlobal.gBrowser.selectedTab;
+          // Save the size of the current tab, since the newly-created tab will
+          // likely be active by the time the promise below resolves and the
+          // event is dispatched.
+          const currentTab = nativeTab.ownerGlobal.gBrowser.selectedTab;
+          const {frameLoader} = currentTab.linkedBrowser;
+          const currentTabSize = {
+            width: frameLoader.lazyWidth,
+            height: frameLoader.lazyHeight,
+          };
 
           // We need to delay sending this event until the next tick, since the
           // tab could have been created with a lazy browser but still not have
           // been assigned a SessionStore tab state with the URL and title.
           Promise.resolve().then(() => {
-            this.emitCreated(event.originalTarget, currentTab);
+            this.emitCreated(event.originalTarget, currentTabSize);
           });
         }
         break;
@@ -584,12 +589,12 @@ class TabTracker extends TabTrackerBase {
    *
    * @param {NativeTab} nativeTab
    *        The tab element which is being created.
-   * @param {NativeTab} [currentTab]
-   *        The tab element for the currently active tab.
+   * @param {Object} [currentTabSize]
+   *        The size of the tab element for the currently active tab.
    * @private
    */
-  emitCreated(nativeTab, currentTab) {
-    this.emit("tab-created", {nativeTab, currentTab});
+  emitCreated(nativeTab, currentTabSize) {
+    this.emit("tab-created", {nativeTab, currentTabSize});
   }
 
   /**

browser/components/extensions/parent/ext-tabs.js

@@ -403,7 +403,7 @@ this.tabs = class extends ExtensionAPI {
           name: "tabs.onCreated",
           register: fire => {
             let listener = (eventName, event) => {
-              fire.async(tabManager.convert(event.nativeTab, event.currentTab));
+              fire.async(tabManager.convert(event.nativeTab, event.currentTabSize));
             };
 
             tabTracker.on("tab-created", listener);
@@ -564,7 +564,12 @@ this.tabs = class extends ExtensionAPI {
             }
 
             tabListener.initTabReady();
-            let currentTab = window.gBrowser.selectedTab;
+            const currentTab = window.gBrowser.selectedTab;
+            const {frameLoader} = currentTab.linkedBrowser;
+            const currentTabSize = {
+              width: frameLoader.lazyWidth,
+              height: frameLoader.lazyHeight,
+            };
 
             if (createProperties.openerTabId !== null) {
               options.ownerTab = tabTracker.getTab(createProperties.openerTabId);
@@ -631,7 +636,7 @@ this.tabs = class extends ExtensionAPI {
               tabListener.initializingTabs.add(nativeTab);
             }
 
-            return tabManager.convert(nativeTab, currentTab);
+            return tabManager.convert(nativeTab, currentTabSize);
           });
         },
 

browser/components/extensions/test/browser/browser_ext_tabs_events.js

@@ -372,3 +372,41 @@ add_task(async function testTabCreateRelated() {
 
   BrowserTestUtils.removeTab(openerTab);
 });
+
+add_task(async function testLastTabRemoval() {
+  await SpecialPowers.pushPrefEnv({set: [
+    ["browser.tabs.closeWindowWithLastTab", false],
+  ]});
+
+  async function background() {
+    let windowId;
+    browser.tabs.onCreated.addListener(tab => {
+      browser.test.assertEq(windowId, tab.windowId,
+                            "expecting onCreated after onRemoved on the same window");
+      browser.test.sendMessage("tabCreated", `${tab.width}x${tab.height}`);
+    });
+    browser.tabs.onRemoved.addListener((tabId, info) => {
+      windowId = info.windowId;
+    });
+  }
+
+  let extension = ExtensionTestUtils.loadExtension({
+    manifest: {
+      "permissions": ["tabs"],
+    },
+    background,
+  });
+
+  let newWin = await BrowserTestUtils.openNewBrowserWindow();
+  await extension.startup();
+
+  const oldBrowser = newWin.gBrowser.selectedBrowser;
+  const expectedDims = `${oldBrowser.clientWidth}x${oldBrowser.clientHeight}`;
+  BrowserTestUtils.removeTab(newWin.gBrowser.selectedTab);
+
+  const actualDims = await extension.awaitMessage("tabCreated");
+  is(actualDims, expectedDims, "created tab reports a size same to the removed last tab");
+
+  await extension.unload();
+  await BrowserTestUtils.closeWindow(newWin);
+});

toolkit/components/extensions/parent/ext-tabs-base.js

@@ -296,7 +296,7 @@ class TabBase {
    *        @readonly
    */
   get frameLoader() {
-    return this.browser.frameLoader;
+    return this.browser && this.browser.frameLoader;
   }
 
   /**
@@ -581,12 +581,12 @@ class TabBase {
    * of its properties which the extension is permitted to access, in the format
    * required to be returned by WebExtension APIs.
    *
-   * @param {Tab} [fallbackTab]
-   *        A tab to retrieve geometry data from if the lazy geometry data for
-   *        this tab hasn't been initialized yet.
+   * @param {Object} [fallbackTabSize]
+   *        A geometry data if the lazy geometry data for this tab hasn't been
+   *        initialized yet.
    * @returns {object}
    */
-  convert(fallbackTab = null) {
+  convert(fallbackTabSize = null) {
     let result = {
       id: this.id,
       index: this.index,
@@ -611,9 +611,9 @@ class TabBase {
 
     // If the tab has not been fully layed-out yet, fallback to the geometry
     // from a different tab (usually the currently active tab).
-    if (fallbackTab && (!result.width || !result.height)) {
-      result.width = fallbackTab.width;
-      result.height = fallbackTab.height;
+    if (fallbackTabSize && (!result.width || !result.height)) {
+      result.width = fallbackTabSize.width;
+      result.height = fallbackTabSize.height;
     }
 
     let opener = this.openerTabId;
@@ -1831,15 +1831,15 @@ class TabManagerBase {
    *
    * @param {NativeTab} nativeTab
    *        The native tab to convert.
-   * @param {NativeTab} [fallbackTab]
-   *        A tab to retrieve geometry data from if the lazy geometry data for
-   *        this tab hasn't been initialized yet.
+   * @param {Object} [fallbackTabSize]
+   *        A geometry data if the lazy geometry data for this tab hasn't been
+   *        initialized yet.
    *
    * @returns {Object}
    */
-  convert(nativeTab, fallbackTab = null) {
+  convert(nativeTab, fallbackTabSize = null) {
     return this.getWrapper(nativeTab)
-               .convert(fallbackTab && this.getWrapper(fallbackTab));
+               .convert(fallbackTabSize);
   }
 
   // The JSDoc validator does not support @returns tags in abstract functions or