Bug 1670134, remove message manager reference from LightweightThemeChild.jsm, by getting chromeOuterWindowId from BrowserChild instead, r=mconley

Differential Revision: https://phabricator.services.mozilla.com/D93043

browser/actors/LightweightThemeChild.jsm

@@ -25,12 +25,17 @@ class LightweightThemeChild extends JSWindowActorChild {
   }
 
   _getChromeOuterWindowID() {
-    if (this.docShell.messageManager) {
-      return this.docShell.messageManager.chromeOuterWindowID;
+    try {
+      // Getting the browserChild throws an exception when it is null.
+      let browserChild = this.docShell.browserChild;
+      if (browserChild) {
+        return browserChild.chromeOuterWindowID;
       }
+    } catch (ex) {}
+
     // We don't have a message manager, so presumable we're running in a sidebar
     // in the parent process.
-    return this.contentWindow.top.docShell.outerWindowID;
+    return this.contentWindow.top.docShell?.outerWindowID;
   }
 
   /**

dom/base/ContentFrameMessageManager.h

@@ -40,7 +40,6 @@ class ContentFrameMessageManager : public DOMEventTargetHelper,
   virtual Nullable<WindowProxyHolder> GetContent(ErrorResult& aError) = 0;
   virtual already_AddRefed<nsIDocShell> GetDocShell(ErrorResult& aError) = 0;
   virtual already_AddRefed<nsIEventTarget> GetTabEventTarget() = 0;
-  virtual uint64_t ChromeOuterWindowID() = 0;
 
   nsFrameMessageManager* GetMessageManager() { return mMessageManager; }
   void DisconnectMessageManager() {

dom/base/InProcessBrowserChildMessageManager.cpp

@@ -186,25 +186,6 @@ InProcessBrowserChildMessageManager::GetTabEventTarget() {
   return target.forget();
 }
 
-uint64_t InProcessBrowserChildMessageManager::ChromeOuterWindowID() {
-  if (!mDocShell) {
-    return 0;
-  }
-
-  nsCOMPtr<nsIDocShellTreeItem> root;
-  nsresult rv = mDocShell->GetInProcessRootTreeItem(getter_AddRefs(root));
-  if (NS_WARN_IF(NS_FAILED(rv))) {
-    return 0;
-  }
-
-  nsPIDOMWindowOuter* topWin = root->GetWindow();
-  if (!topWin) {
-    return 0;
-  }
-
-  return topWin->WindowID();
-}
-
 void InProcessBrowserChildMessageManager::FireUnloadEvent() {
   // We're called from Document::MaybeInitializeFinalizeFrameLoaders, so it
   // should be safe to run script.

dom/base/InProcessBrowserChildMessageManager.h

@@ -62,7 +62,6 @@ class InProcessBrowserChildMessageManager final
     return do_AddRef(mDocShell);
   }
   virtual already_AddRefed<nsIEventTarget> GetTabEventTarget() override;
-  virtual uint64_t ChromeOuterWindowID() override;
 
   NS_FORWARD_SAFE_NSIMESSAGESENDER(mMessageManager)
 

dom/base/test/chrome/test_chromeOuterWindowID.xhtml

@@ -41,13 +41,17 @@ windows.
        "Both browsers should belong to the same document.");
     let winID = getOuterWindowID(browser1.ownerGlobal);
 
-    let browser1ID = await ContentTask.spawn(browser1, null, () => {
-      return chromeOuterWindowID;
-    });
+    let getChildRootOuterId = browser => { 
+      try {
+        return docShell.browserChild?.chromeOuterWindowID;
+      } catch(ex) { }
 
-    let browser2ID = await ContentTask.spawn(browser2, null, () => {
-      return chromeOuterWindowID;
-    });
+      // Not a remote tab
+      return content.top.windowRoot.ownerGlobal.docShell.outerWindowID;
+    };
+
+    let browser1ID = await SpecialPowers.spawn(browser1, [], getChildRootOuterId);
+    let browser2ID = await SpecialPowers.spawn(browser2, [], getChildRootOuterId);
 
     is(browser1ID, winID,
        "Browser 1 frame script environment should have the correct chromeOuterWindowID");

dom/chrome-webidl/MessageManager.webidl

@@ -473,13 +473,6 @@ interface ContentFrameMessageManager : EventTarget
    */
   readonly attribute nsIEventTarget? tabEventTarget;
 
-  /**
-   * Returns the outerWindowID of the browser window hosting the frame.
-   * If, for some reason, the frameloader can't be resolved to a browser
-   * window, this will return 0.
-   */
-  readonly attribute long long chromeOuterWindowID;
-
 };
 ContentFrameMessageManager includes MessageManagerGlobal;
 ContentFrameMessageManager includes SyncMessageSenderMixin;

dom/interfaces/base/nsIBrowserChild.idl

@@ -50,4 +50,9 @@ interface nsIBrowserChild : nsISupports
    * nsIWebNavigation navigation finished in the child.
    */
   void notifyNavigationFinished();
+
+  /**
+   * Id of the chrome window the tab is within.
+   */
+  readonly attribute uint64_t chromeOuterWindowID;
 };

dom/ipc/BrowserChild.cpp

@@ -2993,6 +2993,12 @@ void BrowserChild::SetTabId(const TabId& aTabId) {
   NestedBrowserChildMap()[mUniqueId] = this;
 }
 
+NS_IMETHODIMP
+BrowserChild::GetChromeOuterWindowID(uint64_t* aId) {
+  *aId = ChromeOuterWindowID();
+  return NS_OK;
+}
+
 bool BrowserChild::DoSendBlockingMessage(
     const nsAString& aMessage, StructuredCloneData& aData,
     nsTArray<StructuredCloneData>* aRetVal) {
@@ -4024,13 +4030,6 @@ BrowserChildMessageManager::GetTabEventTarget() {
   return target.forget();
 }
 
-uint64_t BrowserChildMessageManager::ChromeOuterWindowID() {
-  if (!mBrowserChild) {
-    return 0;
-  }
-  return mBrowserChild->ChromeOuterWindowID();
-}
-
 nsresult BrowserChildMessageManager::Dispatch(
     TaskCategory aCategory, already_AddRefed<nsIRunnable>&& aRunnable) {
   return DispatcherTrait::Dispatch(aCategory, std::move(aRunnable));

dom/ipc/BrowserChild.h

@@ -106,7 +106,6 @@ class BrowserChildMessageManager : public ContentFrameMessageManager,
   virtual already_AddRefed<nsIDocShell> GetDocShell(
       ErrorResult& aError) override;
   virtual already_AddRefed<nsIEventTarget> GetTabEventTarget() override;
-  virtual uint64_t ChromeOuterWindowID() override;
 
   NS_FORWARD_SAFE_NSIMESSAGESENDER(mMessageManager)