Bug 1136322 - Optimize anon scopes from CC graph, r=mccr8

dom/base/ProcessGlobal.cpp

@@ -41,6 +41,7 @@ ProcessGlobal::Get()
 NS_IMETHODIMP_(bool)
 ProcessGlobal::MarkForCC()
 {
+  MarkScopesForCC();
   return mMessageManager ? mMessageManager->MarkForCC() : false;
 }
 

dom/base/nsFrameMessageManager.cpp

@@ -1682,6 +1682,17 @@ nsMessageManagerScriptExecutor::InitChildGlobalInternal(
   return true;
 }
 
+void
+nsMessageManagerScriptExecutor::MarkScopesForCC()
+{
+  for (uint32_t i = 0; i < mAnonymousGlobalScopes.Length(); ++i) {
+    JSObject* obj = mAnonymousGlobalScopes[i];
+    if (obj) {
+      JS::ExposeObjectToActiveJS(obj);
+    }
+  }
+}
+
 NS_IMPL_ISUPPORTS(nsScriptCacheCleaner, nsIObserver)
 
 nsFrameMessageManager* nsFrameMessageManager::sChildProcessManager = nullptr;

dom/base/nsFrameMessageManager.h

@@ -401,6 +401,8 @@ public:
     nsCOMPtr<nsIXPConnectJSObjectHolder> ref = mGlobal;
     return ref.forget();
   }
+
+  void MarkScopesForCC();
 protected:
   friend class nsMessageManagerScriptCx;
   nsMessageManagerScriptExecutor() { MOZ_COUNT_CTOR(nsMessageManagerScriptExecutor); }

dom/base/nsInProcessTabChildGlobal.cpp

@@ -129,6 +129,7 @@ nsInProcessTabChildGlobal::~nsInProcessTabChildGlobal()
 NS_IMETHODIMP_(bool)
 nsInProcessTabChildGlobal::MarkForCC()
 {
+  MarkScopesForCC();
   return mMessageManager ? mMessageManager->MarkForCC() : false;
 }
 

dom/ipc/TabChild.cpp

@@ -3202,6 +3202,9 @@ NS_IMPL_RELEASE_INHERITED(TabChildGlobal, DOMEventTargetHelper)
 NS_IMETHODIMP_(bool)
 TabChildGlobal::MarkForCC()
 {
+  if (mTabChild) {
+    mTabChild->MarkScopesForCC();
+  }
   return mMessageManager ? mMessageManager->MarkForCC() : false;
 }