Bug 793517 - Make nsDOMEventTargetHelper to unmark listeners during canSkip, r=mccr8

content/events/src/nsDOMEventTargetHelper.cpp

@@ -43,6 +43,23 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsDOMEventTargetHelper)
   NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMPTR(mListenerManager)
 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
 
+NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_BEGIN(nsDOMEventTargetHelper)
+  if (tmp->IsBlack()) {
+    if (tmp->mListenerManager) {
+      tmp->mListenerManager->UnmarkGrayJSListeners();
+    }
+    return true;
+  }
+NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_END
+
+NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_IN_CC_BEGIN(nsDOMEventTargetHelper)
+  return tmp->IsBlack();
+NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_IN_CC_END
+
+NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_THIS_BEGIN(nsDOMEventTargetHelper)
+  return tmp->IsBlack();
+NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_THIS_END
+
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsDOMEventTargetHelper)
   NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
   NS_INTERFACE_MAP_ENTRY(nsISupports)

content/events/src/nsDOMEventTargetHelper.h

@@ -26,7 +26,7 @@ public:
   nsDOMEventTargetHelper() : mOwner(nullptr), mHasOrHasHadOwner(false) {}
   virtual ~nsDOMEventTargetHelper();
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
-  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(nsDOMEventTargetHelper)
+  NS_DECL_CYCLE_COLLECTION_SKIPPABLE_SCRIPT_HOLDER_CLASS(nsDOMEventTargetHelper)
 
   NS_DECL_NSIDOMEVENTTARGET
   void AddEventListener(const nsAString& aType,

dom/src/events/nsJSEventListener.cpp

@@ -70,7 +70,16 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsJSEventListener)
     NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMPTR(mContext)
   }
 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
-NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsJSEventListener)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INTERNAL(nsJSEventListener)
+  if (NS_UNLIKELY(cb.WantDebugInfo()) && tmp->mEventName) {
+    nsAutoCString name;
+    name.AppendLiteral("nsJSEventListener handlerName=");
+    name.Append(
+      NS_ConvertUTF16toUTF8(nsDependentAtomString(tmp->mEventName)).get());
+    cb.DescribeRefCountedNode(tmp->mRefCnt.get(), name.get());
+  } else {
+    NS_IMPL_CYCLE_COLLECTION_DESCRIBE(nsJSEventListener, tmp->mRefCnt.get())
+  }
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMPTR(mContext)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END