Bug 1373857 - Part 2: Add some AsyncEventDispatcher helpers for dispatching WidgetEvents directly; r=smaug

dom/events/AsyncEventDispatcher.cpp

@@ -22,12 +22,14 @@ using namespace dom;
 
 AsyncEventDispatcher::AsyncEventDispatcher(EventTarget* aTarget,
                                            WidgetEvent& aEvent)
-  : mTarget(aTarget)
+  : mTarget(aTarget),
+    mEventMessage(eUnidentifiedEvent)
 {
   MOZ_ASSERT(mTarget);
   RefPtr<Event> event =
     EventDispatcher::CreateEvent(aTarget, nullptr, &aEvent, EmptyString());
   mEvent = event.forget();
+  mEventType.SetIsVoid(true);
   NS_ASSERTION(mEvent, "Should never fail to create an event");
   mEvent->DuplicatePrivateData();
   mEvent->SetTrusted(aEvent.IsTrusted());
@@ -39,14 +41,20 @@ AsyncEventDispatcher::Run()
   if (mCanceled) {
     return NS_OK;
   }
+  nsCOMPtr<nsINode> node = do_QueryInterface(mTarget);
   if (mCheckStillInDoc) {
-    nsCOMPtr<nsINode> node = do_QueryInterface(mTarget);
     MOZ_ASSERT(node);
     if (!node->IsInComposedDoc()) {
       return NS_OK;
     }
   }
   mTarget->AsyncEventRunning(this);
+  if (mEventMessage != eUnidentifiedEvent) {
+    return nsContentUtils::DispatchTrustedEvent<WidgetEvent>
+      (node->OwnerDoc(), mTarget, mEventMessage, mBubbles,
+       false /* aCancelable */, nullptr /* aDefaultAction */,
+       mOnlyChromeDispatch);
+  }
   RefPtr<Event> event = mEvent ? mEvent->InternalDOMEvent() : nullptr;
   if (!event) {
     event = NS_NewDOMEvent(mTarget, nullptr, nullptr);

dom/events/AsyncEventDispatcher.h

@@ -38,22 +38,54 @@ public:
                        bool aBubbles, bool aOnlyChromeDispatch)
     : mTarget(aTarget)
     , mEventType(aEventType)
+    , mEventMessage(eUnidentifiedEvent)
     , mBubbles(aBubbles)
     , mOnlyChromeDispatch(aOnlyChromeDispatch)
   {
   }
 
+  /**
+   * If aOnlyChromeDispatch is true, the event is dispatched to only
+   * chrome node. In that case, if aTarget is already a chrome node,
+   * the event is dispatched to it, otherwise the dispatch path starts
+   * at the first chrome ancestor of that target.
+   */
+  AsyncEventDispatcher(nsINode* aTarget,
+                       mozilla::EventMessage aEventMessage,
+                       bool aBubbles, bool aOnlyChromeDispatch)
+    : mTarget(aTarget)
+    , mEventMessage(aEventMessage)
+    , mBubbles(aBubbles)
+    , mOnlyChromeDispatch(aOnlyChromeDispatch)
+  {
+    mEventType.SetIsVoid(true);
+    MOZ_ASSERT(mEventMessage != eUnidentifiedEvent);
+  }
+
   AsyncEventDispatcher(dom::EventTarget* aTarget, const nsAString& aEventType,
                        bool aBubbles)
     : mTarget(aTarget)
     , mEventType(aEventType)
+    , mEventMessage(eUnidentifiedEvent)
     , mBubbles(aBubbles)
   {
   }
 
+  AsyncEventDispatcher(dom::EventTarget* aTarget,
+                       mozilla::EventMessage aEventMessage,
+                       bool aBubbles)
+    : mTarget(aTarget)
+    , mEventMessage(aEventMessage)
+    , mBubbles(aBubbles)
+  {
+    mEventType.SetIsVoid(true);
+    MOZ_ASSERT(mEventMessage != eUnidentifiedEvent);
+  }
+
   AsyncEventDispatcher(dom::EventTarget* aTarget, nsIDOMEvent* aEvent)
     : mTarget(aTarget)
     , mEvent(aEvent)
+    , mEventMessage(eUnidentifiedEvent)
   {
   }
 
@@ -71,7 +103,11 @@ public:
 
   nsCOMPtr<dom::EventTarget> mTarget;
   nsCOMPtr<nsIDOMEvent> mEvent;
+  // If mEventType is set, mEventMessage will be eUnidentifiedEvent.
+  // If mEventMessage is set, mEventType will be void.
+  // They can never both be set at the same time.
   nsString              mEventType;
+  mozilla::EventMessage mEventMessage;
   bool                  mBubbles = false;
   bool                  mOnlyChromeDispatch = false;
   bool                  mCanceled = false;