Bug 1479569 part 1. Add a ContentFrameMessageManager getter on nsIDocShell. r=kmag

docshell/base/nsDocShell.cpp

@@ -39,6 +39,7 @@
 #include "mozilla/dom/ClientManager.h"
 #include "mozilla/dom/ClientSource.h"
 #include "mozilla/dom/ContentChild.h"
+#include "mozilla/dom/ContentFrameMessageManager.h"
 #include "mozilla/dom/DocGroup.h"
 #include "mozilla/dom/Element.h"
 #include "mozilla/dom/HTMLAnchorElement.h"
@@ -639,16 +640,10 @@ nsDocShell::GetInterface(const nsIID& aIID, void** aSink)
     *aSink = GetTabChild().take();
     return *aSink ? NS_OK : NS_ERROR_FAILURE;
   } else if (aIID.Equals(NS_GET_IID(nsIContentFrameMessageManager))) {
-    RefPtr<TabChild> tabChild = TabChild::GetFrom(this);
-    nsCOMPtr<nsIContentFrameMessageManager> mm;
-    if (tabChild) {
-      mm = tabChild->GetMessageManager();
-    } else {
-      if (nsPIDOMWindowOuter* win = GetWindow()) {
-        mm = do_QueryInterface(win->GetParentTarget());
-      }
-    }
-    *aSink = mm.get();
+    RefPtr<ContentFrameMessageManager> mm = GetMessageManager();
+    nsCOMPtr<nsIContentFrameMessageManager> mm2 = do_QueryObject(mm);
+    mm2.forget(aSink);
+    return *aSink ? NS_OK : NS_NOINTERFACE;
   } else {
     return nsDocLoader::GetInterface(aIID, aSink);
   }
@@ -3976,6 +3971,19 @@ nsDocShell::GetDomWindow(mozIDOMWindowProxy** aWindow)
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsDocShell::GetMessageManager(ContentFrameMessageManager** aMessageManager)
+{
+  RefPtr<ContentFrameMessageManager> mm;
+  if (RefPtr<TabChild> tabChild = TabChild::GetFrom(this)) {
+    mm = tabChild->GetMessageManager();
+  } else if (nsPIDOMWindowOuter* win = GetWindow()) {
+    mm = win->GetMessageManager();
+  }
+  mm.forget(aMessageManager);
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 nsDocShell::SetDeviceSizeIsPageSize(bool aValue)
 {

docshell/base/nsIDocShell.idl

@@ -65,6 +65,7 @@ interface nsILoadURIDelegate;
 native TabChildRef(already_AddRefed<nsITabChild>);
 native nsDocShellLoadInfoPtr(nsDocShellLoadInfo*);
 
+webidl ContentFrameMessageManager;
 webidl EventTarget;
 
 [scriptable, builtinclass, uuid(049234fe-da10-478b-bc5d-bc6f9a1ba63d)]
@@ -1200,4 +1201,10 @@ interface nsIDocShell : nsIDocShellTreeItem
    * Media queries only look at the value in the top-most docshell.
    */
   attribute unsigned long displayMode;
+
+  /**
+   * The message manager for this docshell.  This does not throw, but
+   * can return null if the docshell has no message manager.
+   */
+  [infallible] readonly attribute ContentFrameMessageManager messageManager;
 };

dom/base/nsCCUncollectableMarker.cpp

@@ -31,6 +31,7 @@
 #include "mozilla/CycleCollectedJSRuntime.h"
 #include "mozilla/EventListenerManager.h"
 #include "mozilla/dom/ChromeMessageBroadcaster.h"
+#include "mozilla/dom/ContentFrameMessageManager.h"
 #include "mozilla/dom/Element.h"
 #include "mozilla/dom/ParentProcessMessageManager.h"
 #include "mozilla/dom/ProcessGlobal.h"
@@ -119,11 +120,11 @@ MarkChildMessageManagers(MessageBroadcaster* aMM)
     mozilla::dom::ipc::MessageManagerCallback* cb = tabMM->GetCallback();
     if (cb) {
       nsFrameLoader* fl = static_cast<nsFrameLoader*>(cb);
-      EventTarget* et = fl->GetTabChildGlobalAsEventTarget();
+      nsInProcessTabChildGlobal* et = fl->GetTabChildGlobal();
       if (!et) {
         continue;
       }
-      static_cast<nsInProcessTabChildGlobal*>(et)->MarkForCC();
+      et->MarkForCC();
       EventListenerManager* elm = et->GetExistingListenerManager();
       if (elm) {
         elm->MarkForCC();

dom/base/nsContentUtils.cpp

@@ -121,6 +121,7 @@
 #include "nsHtml5StringParser.h"
 #include "nsHTMLDocument.h"
 #include "nsHTMLTags.h"
+#include "nsInProcessTabChildGlobal.h"
 #include "nsIAddonPolicyService.h"
 #include "nsIAnonymousContentCreator.h"
 #include "nsIAsyncVerifyRedirectCallback.h"
@@ -11087,8 +11088,8 @@ nsContentUtils::ContentIsLink(nsIContent* aContent)
       kNameSpaceID_XLink, nsGkAtoms::type, nsGkAtoms::simple, eCaseMatters);
 }
 
-/* static */ already_AddRefed<EventTarget>
-nsContentUtils::TryGetTabChildGlobalAsEventTarget(nsISupports* aFrom)
+/* static */ already_AddRefed<ContentFrameMessageManager>
+nsContentUtils::TryGetTabChildGlobal(nsISupports* aFrom)
 {
   nsCOMPtr<nsIFrameLoaderOwner> frameLoaderOwner = do_QueryInterface(aFrom);
   if (!frameLoaderOwner) {
@@ -11100,8 +11101,8 @@ nsContentUtils::TryGetTabChildGlobalAsEventTarget(nsISupports* aFrom)
     return nullptr;
   }
 
-  nsCOMPtr<EventTarget> target = frameLoader->GetTabChildGlobalAsEventTarget();
-  return target.forget();
+  RefPtr<ContentFrameMessageManager> manager = frameLoader->GetTabChildGlobal();
+  return manager.forget();
 }
 
 /* static */ uint32_t

dom/base/nsContentUtils.h

@@ -124,6 +124,7 @@ class EventListenerManager;
 class HTMLEditor;
 
 namespace dom {
+class ContentFrameMessageManager;
 struct CustomElementDefinition;
 class DocumentFragment;
 class Element;
@@ -3242,8 +3243,8 @@ public:
 
   static bool ContentIsLink(nsIContent* aContent);
 
-  static already_AddRefed<mozilla::dom::EventTarget>
-  TryGetTabChildGlobalAsEventTarget(nsISupports* aFrom);
+  static already_AddRefed<mozilla::dom::ContentFrameMessageManager>
+  TryGetTabChildGlobal(nsISupports* aFrom);
 
   static PopupControlState
   PushPopupControlState(PopupControlState aState, bool aForce)

dom/base/nsFrameLoader.cpp

@@ -2820,8 +2820,7 @@ nsFrameLoader::DoLoadMessageManagerScript(const nsAString& aURL, bool aRunInGlob
   if (tabParent) {
     return tabParent->SendLoadRemoteScript(nsString(aURL), aRunInGlobalScope);
   }
-  RefPtr<nsInProcessTabChildGlobal> tabChild =
-    static_cast<nsInProcessTabChildGlobal*>(GetTabChildGlobalAsEventTarget());
+  RefPtr<nsInProcessTabChildGlobal> tabChild = GetTabChildGlobal();
   if (tabChild) {
     tabChild->LoadFrameScript(aURL, aRunInGlobalScope);
   }
@@ -2979,12 +2978,6 @@ nsFrameLoader::ReallyLoadFrameScripts()
   return NS_OK;
 }
 
-EventTarget*
-nsFrameLoader::GetTabChildGlobalAsEventTarget()
-{
-  return mChildMessageManager.get();
-}
-
 already_AddRefed<Element>
 nsFrameLoader::GetOwnerElement()
 {

dom/base/nsFrameLoader.h

@@ -106,7 +106,10 @@ public:
   void DestroyDocShell();
   void DestroyComplete();
   nsIDocShell* GetExistingDocShell() { return mDocShell; }
-  mozilla::dom::EventTarget* GetTabChildGlobalAsEventTarget();
+  nsInProcessTabChildGlobal* GetTabChildGlobal() const
+  {
+    return mChildMessageManager;
+  }
   nsresult CreateStaticClone(nsFrameLoader* aDest);
   nsresult UpdatePositionAndSize(nsSubDocumentFrame *aIFrame);
 

dom/base/nsGlobalWindowInner.cpp

@@ -18,6 +18,7 @@
 #include "nsDOMNavigationTiming.h"
 #include "nsIDOMStorageManager.h"
 #include "mozilla/AutoplayPermissionManager.h"
+#include "mozilla/dom/ContentFrameMessageManager.h"
 #include "mozilla/dom/DOMJSProxyHandler.h"
 #include "mozilla/dom/DOMPrefs.h"
 #include "mozilla/dom/EventTarget.h"
@@ -1910,20 +1911,18 @@ nsGlobalWindowInner::UpdateParentTarget()
 
   nsCOMPtr<Element> frameElement = GetOuterWindow()->GetFrameElementInternal();
   nsCOMPtr<EventTarget> eventTarget =
-    nsContentUtils::TryGetTabChildGlobalAsEventTarget(frameElement);
+    nsContentUtils::TryGetTabChildGlobal(frameElement);
 
   if (!eventTarget) {
     nsGlobalWindowOuter* topWin = GetScriptableTopInternal();
     if (topWin) {
       frameElement = topWin->AsOuter()->GetFrameElementInternal();
-      eventTarget =
-        nsContentUtils::TryGetTabChildGlobalAsEventTarget(frameElement);
+      eventTarget = nsContentUtils::TryGetTabChildGlobal(frameElement);
     }
   }
 
   if (!eventTarget) {
-    eventTarget =
-      nsContentUtils::TryGetTabChildGlobalAsEventTarget(mChromeEventHandler);
+    eventTarget = nsContentUtils::TryGetTabChildGlobal(mChromeEventHandler);
   }
 
   if (!eventTarget) {

dom/base/nsGlobalWindowOuter.cpp

@@ -20,6 +20,7 @@
 #include "nsISecureBrowserUI.h"
 #include "nsIWebProgressListener.h"
 #include "mozilla/AntiTrackingCommon.h"
+#include "mozilla/dom/ContentFrameMessageManager.h"
 #include "mozilla/dom/EventTarget.h"
 #include "mozilla/dom/LocalStorage.h"
 #include "mozilla/dom/Storage.h"
@@ -1038,6 +1039,7 @@ nsGlobalWindowOuter::CleanUp()
   }
   mChromeEventHandler = nullptr; // Forces Release
   mParentTarget = nullptr;
+  mMessageManager = nullptr;
 
   mArguments = nullptr;
 
@@ -1144,6 +1146,7 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INTERNAL(nsGlobalWindowOuter)
   // Traverse stuff from nsPIDOMWindow
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mChromeEventHandler)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mParentTarget)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mMessageManager)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mFrameElement)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mOpenerForInitialContentBrowser)
 
@@ -1170,6 +1173,7 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsGlobalWindowOuter)
   // Unlink stuff from nsPIDOMWindow
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mChromeEventHandler)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mParentTarget)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mMessageManager)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mFrameElement)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mOpenerForInitialContentBrowser)
 
@@ -2236,9 +2240,10 @@ nsGlobalWindowOuter::SetOpenerWindow(nsPIDOMWindowOuter* aOpener,
 void
 nsGlobalWindowOuter::UpdateParentTarget()
 {
-  // NOTE: This method is identical to
+  // NOTE: This method is nearly identical to
   // nsGlobalWindowInner::UpdateParentTarget(). IF YOU UPDATE THIS METHOD,
-  // UPDATE THE OTHER ONE TOO!
+  // UPDATE THE OTHER ONE TOO!  The one difference is that this method updates
+  // mMessageManager as well, which inner windows don't have.
 
   // Try to get our frame element's tab child global (its in-process message
   // manager).  If that fails, fall back to the chrome event handler's tab
@@ -2246,28 +2251,25 @@ nsGlobalWindowOuter::UpdateParentTarget()
   // handler itself.
 
   nsCOMPtr<Element> frameElement = GetOuterWindow()->GetFrameElementInternal();
-  nsCOMPtr<EventTarget> eventTarget =
-    nsContentUtils::TryGetTabChildGlobalAsEventTarget(frameElement);
+  mMessageManager = nsContentUtils::TryGetTabChildGlobal(frameElement);
 
-  if (!eventTarget) {
+  if (!mMessageManager) {
     nsGlobalWindowOuter* topWin = GetScriptableTopInternal();
     if (topWin) {
       frameElement = topWin->GetFrameElementInternal();
-      eventTarget =
-        nsContentUtils::TryGetTabChildGlobalAsEventTarget(frameElement);
+      mMessageManager = nsContentUtils::TryGetTabChildGlobal(frameElement);
     }
   }
 
-  if (!eventTarget) {
-    eventTarget =
-      nsContentUtils::TryGetTabChildGlobalAsEventTarget(mChromeEventHandler);
+  if (!mMessageManager) {
+    mMessageManager = nsContentUtils::TryGetTabChildGlobal(mChromeEventHandler);
   }
 
-  if (!eventTarget) {
-    eventTarget = mChromeEventHandler;
+  if (mMessageManager) {
+    mParentTarget = mMessageManager;
+  } else {
+    mParentTarget = mChromeEventHandler;
   }
-
-  mParentTarget = eventTarget;
 }
 
 EventTarget*
@@ -7627,6 +7629,19 @@ nsPIDOMWindowOuter::MaybeCreateDoc()
   }
 }
 
+void
+nsPIDOMWindowOuter::SetChromeEventHandlerInternal(EventTarget* aChromeEventHandler)
+{
+  // Out-of-line so we don't need to include ContentFrameMessageManager.h in
+  // nsPIDOMWindow.h.
+  mChromeEventHandler = aChromeEventHandler;
+
+  // mParentTarget and mMessageManager will be set when the next event is
+  // dispatched or someone asks for our message manager.
+  mParentTarget = nullptr;
+  mMessageManager = nullptr;
+}
+
 mozilla::dom::DocGroup*
 nsPIDOMWindowOuter::GetDocGroup() const
 {

dom/base/nsInProcessTabChildGlobal.cpp

@@ -295,7 +295,7 @@ nsInProcessTabChildGlobal::GetEventTargetParent(EventChainPreVisitor& aVisitor)
     nsCOMPtr<nsIFrameLoaderOwner> owner = do_QueryInterface(mOwner);
     RefPtr<nsFrameLoader> fl = owner->GetFrameLoader();
     if (fl) {
-      NS_ASSERTION(this == fl->GetTabChildGlobalAsEventTarget(),
+      NS_ASSERTION(this == fl->GetTabChildGlobal(),
                    "Wrong event target!");
       NS_ASSERTION(fl->mMessageManager == mChromeMessageManager,
                    "Wrong message manager!");

dom/base/nsPIDOMWindow.h

@@ -51,6 +51,7 @@ namespace dom {
 class AudioContext;
 class ClientInfo;
 class ClientState;
+class ContentFrameMessageManager;
 class DocGroup;
 class TabGroup;
 class Element;
@@ -872,6 +873,15 @@ public:
     return mParentTarget;
   }
 
+  mozilla::dom::ContentFrameMessageManager* GetMessageManager()
+  {
+    // We maintain our mMessageManager state alongside mParentTarget.
+    if (!mParentTarget) {
+      UpdateParentTarget();
+    }
+    return mMessageManager;
+  }
+
   nsIDocument* GetExtantDoc() const
   {
     return mDoc;
@@ -1160,11 +1170,7 @@ protected:
   // we have what it takes to do so.
   void MaybeCreateDoc();
 
-  void SetChromeEventHandlerInternal(mozilla::dom::EventTarget* aChromeEventHandler) {
-    mChromeEventHandler = aChromeEventHandler;
-    // mParentTarget will be set when the next event is dispatched.
-    mParentTarget = nullptr;
-  }
+  void SetChromeEventHandlerInternal(mozilla::dom::EventTarget* aChromeEventHandler);
 
   virtual void UpdateParentTarget() = 0;
 
@@ -1177,6 +1183,7 @@ protected:
   nsCOMPtr<nsIURI> mDocumentURI; // strong
 
   nsCOMPtr<mozilla::dom::EventTarget> mParentTarget; // strong
+  RefPtr<mozilla::dom::ContentFrameMessageManager> mMessageManager; // strong
 
   nsCOMPtr<mozilla::dom::Element> mFrameElement;