Bug 1041425 - Enable fast-path dispatch when sending touch event to nested oop iframe. r=smaug

dom/ipc/TabChild.cpp

@@ -11,6 +11,7 @@
 #include "Layers.h"
 #include "ContentChild.h"
 #include "IndexedDBChild.h"
+#include "TabParent.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/ClearOnShutdown.h"
 #include "mozilla/EventListenerManager.h"
@@ -533,6 +534,11 @@ TabChildBase::DispatchWidgetEvent(WidgetGUIEvent& event)
   if (!event.widget)
     return nsEventStatus_eConsumeNoDefault;
 
+  if (TabParent* capturer = TabParent::GetEventCapturer()) {
+    if (capturer->TryCapture(event)) {
+      return nsEventStatus_eConsumeNoDefault;
+    }
+  }
   nsEventStatus status;
   NS_ENSURE_SUCCESS(event.widget->DispatchEvent(&event, status),
                     nsEventStatus_eConsumeNoDefault);