Bug 1003934 - Forward NS_MOUSE_EXIT events to content processes so they know the mouse has exited their frame. r=smaug

dom/events/EventStateManager.cpp

@@ -1144,6 +1144,7 @@ CrossProcessSafeEvent(const WidgetEvent& aEvent)
     case NS_MOUSE_BUTTON_UP:
     case NS_MOUSE_MOVE:
     case NS_CONTEXTMENU:
+    case NS_MOUSE_EXIT:
       return true;
     default:
       return false;
@@ -1165,7 +1166,6 @@ CrossProcessSafeEvent(const WidgetEvent& aEvent)
 
 bool
 EventStateManager::HandleCrossProcessEvent(WidgetEvent* aEvent,
-                                           nsIFrame* aTargetFrame,
                                            nsEventStatus *aStatus) {
   if (*aStatus == nsEventStatus_eConsumeNoDefault ||
       aEvent->mFlags.mNoCrossProcessBoundaryForwarding ||
@@ -2655,7 +2655,6 @@ EventStateManager::PostHandleEvent(nsPresContext* aPresContext,
   NS_ENSURE_ARG_POINTER(aStatus);
 
   bool dispatchedToContentProcess = HandleCrossProcessEvent(aEvent,
-                                                            aTargetFrame,
                                                             aStatus);
 
   mCurrentTarget = aTargetFrame;
@@ -3542,6 +3541,44 @@ EventStateManager::IsHandlingUserInput()
          (TimeStamp::Now() - sHandlingInputStart) <= timeout;
 }
 
+static void
+CreateMouseOrPointerWidgetEvent(WidgetMouseEvent* aMouseEvent,
+                                uint32_t aMessage,
+                                nsIContent* aRelatedContent,
+                                nsAutoPtr<WidgetMouseEvent>& aNewEvent)
+{
+  WidgetPointerEvent* sourcePointer = aMouseEvent->AsPointerEvent();
+  if (sourcePointer) {
+    PROFILER_LABEL("Input", "DispatchPointerEvent");
+    nsAutoPtr<WidgetPointerEvent> newPointerEvent;
+    newPointerEvent =
+      new WidgetPointerEvent(aMouseEvent->mFlags.mIsTrusted, aMessage,
+                             aMouseEvent->widget);
+    newPointerEvent->isPrimary = sourcePointer->isPrimary;
+    newPointerEvent->pointerId = sourcePointer->pointerId;
+    newPointerEvent->width = sourcePointer->width;
+    newPointerEvent->height = sourcePointer->height;
+    newPointerEvent->inputSource = sourcePointer->inputSource;
+    newPointerEvent->relatedTarget =
+      nsIPresShell::GetPointerCapturingContent(sourcePointer->pointerId)
+        ? nullptr
+        : aRelatedContent;
+    aNewEvent = newPointerEvent.forget();
+  } else {
+    aNewEvent =
+      new WidgetMouseEvent(aMouseEvent->mFlags.mIsTrusted, aMessage,
+                           aMouseEvent->widget, WidgetMouseEvent::eReal);
+    aNewEvent->relatedTarget = aRelatedContent;
+  }
+  aNewEvent->refPoint = aMouseEvent->refPoint;
+  aNewEvent->modifiers = aMouseEvent->modifiers;
+  aNewEvent->button = aMouseEvent->button;
+  aNewEvent->buttons = aMouseEvent->buttons;
+  aNewEvent->pressure = aMouseEvent->pressure;
+  aNewEvent->pluginEvent = aMouseEvent->pluginEvent;
+  aNewEvent->inputSource = aMouseEvent->inputSource;
+}
+
 nsIFrame*
 EventStateManager::DispatchMouseOrPointerEvent(WidgetMouseEvent* aMouseEvent,
                                                uint32_t aMessage,
@@ -3567,54 +3604,49 @@ EventStateManager::DispatchMouseOrPointerEvent(WidgetMouseEvent* aMouseEvent,
     return mPresContext->GetPrimaryFrameFor(content);
   }
 
-  nsEventStatus status = nsEventStatus_eIgnore;
-  nsAutoPtr<WidgetMouseEvent> event;
-  WidgetPointerEvent* sourcePointer = aMouseEvent->AsPointerEvent();
-  if (sourcePointer) {
-    PROFILER_LABEL("Input", "DispatchPointerEvent");
-    nsAutoPtr<WidgetPointerEvent> newPointerEvent;
-    newPointerEvent =
-      new WidgetPointerEvent(aMouseEvent->mFlags.mIsTrusted, aMessage,
-                             aMouseEvent->widget);
-    newPointerEvent->isPrimary = sourcePointer->isPrimary;
-    newPointerEvent->pointerId = sourcePointer->pointerId;
-    newPointerEvent->width = sourcePointer->width;
-    newPointerEvent->height = sourcePointer->height;
-    newPointerEvent->inputSource = sourcePointer->inputSource;
-    newPointerEvent->relatedTarget = nsIPresShell::GetPointerCapturingContent(sourcePointer->pointerId)
-                                       ? nullptr
-                                       : aRelatedContent;
-    event = newPointerEvent.forget();
-  } else {
-    PROFILER_LABEL("Input", "DispatchMouseEvent");
-    event =
-      new WidgetMouseEvent(aMouseEvent->mFlags.mIsTrusted, aMessage,
-                           aMouseEvent->widget, WidgetMouseEvent::eReal);
-    event->relatedTarget = aRelatedContent;
+  mCurrentTargetContent = nullptr;
+
+  if (!aTargetContent) {
+    return nullptr;
   }
-  event->refPoint = aMouseEvent->refPoint;
-  event->modifiers = aMouseEvent->modifiers;
-  event->button = aMouseEvent->button;
-  event->buttons = aMouseEvent->buttons;
-  event->pressure = aMouseEvent->pressure;
-  event->pluginEvent = aMouseEvent->pluginEvent;
-  event->inputSource = aMouseEvent->inputSource;
+
+  nsAutoPtr<WidgetMouseEvent> dispatchEvent;
+  CreateMouseOrPointerWidgetEvent(aMouseEvent, aMessage,
+                                  aRelatedContent, dispatchEvent);
 
   nsWeakFrame previousTarget = mCurrentTarget;
-
   mCurrentTargetContent = aTargetContent;
 
   nsIFrame* targetFrame = nullptr;
-  if (aTargetContent) {
-    ESMEventCB callback(aTargetContent);
-    EventDispatcher::Dispatch(aTargetContent, mPresContext, event, nullptr,
-                              &status, &callback);
 
-    // Although the primary frame was checked in event callback, 
-    // it may not be the same object after event dispatching and handling.
-    // So we need to refetch it.
-    if (mPresContext) {
-      targetFrame = mPresContext->GetPrimaryFrameFor(aTargetContent);
+  if (aMouseEvent->AsMouseEvent()) {
+    PROFILER_LABEL("Input", "DispatchMouseEvent");
+  }
+
+  nsEventStatus status = nsEventStatus_eIgnore;
+  ESMEventCB callback(aTargetContent);
+  EventDispatcher::Dispatch(aTargetContent, mPresContext, dispatchEvent, nullptr,
+                            &status, &callback);
+
+  if (mPresContext) {
+    // Although the primary frame was checked in event callback, it may not be
+    // the same object after event dispatch and handling, so refetch it.
+    targetFrame = mPresContext->GetPrimaryFrameFor(aTargetContent);
+
+    // If we are leaving remote content, dispatch a mouse exit event to the
+    // remote frame.
+    if (aMessage == NS_MOUSE_EXIT_SYNTH && IsRemoteTarget(aTargetContent)) {
+      // For remote content, send a normal widget mouse exit event.
+      nsAutoPtr<WidgetMouseEvent> remoteEvent;
+      CreateMouseOrPointerWidgetEvent(aMouseEvent, NS_MOUSE_EXIT,
+                                      aRelatedContent, remoteEvent);
+
+      // mCurrentTarget is set to the new target, so we must reset it to the
+      // old target and then dispatch a cross-process event. (mCurrentTarget
+      // will be set back below.) HandleCrossProcessEvent will query for the
+      // proper target via GetEventTarget which will return mCurrentTarget.
+      mCurrentTarget = targetFrame;
+      HandleCrossProcessEvent(remoteEvent, &status);
     }
   }
 

dom/events/EventStateManager.h

@@ -783,7 +783,6 @@ protected:
                                  nsFrameLoader* aRemote,
                                  nsEventStatus *aStatus);
   bool HandleCrossProcessEvent(WidgetEvent* aEvent,
-                               nsIFrame* aTargetFrame,
                                nsEventStatus* aStatus);
 
   void ReleaseCurrentIMEContentObserver();