Fix crash which occurs when a widget destroys itself as a result of ET_GESTURE_TAP_DOWN

ui/views/widget/root_view.h

Index: ui/views/widget/root_view.h
diff --git a/ui/views/widget/root_view.h b/ui/views/widget/root_view.h
index 6ab367bd9923336fb4dd5e0c323b501efb5226ed..2d44169ad7e9a6c2814eaf1ca379a4d3eeda0229 100644
--- a/ui/views/widget/root_view.h
+++ b/ui/views/widget/root_view.h
@@ -145,7 +145,8 @@ class VIEWS_EXPORT RootView : public View,
   // be applied to the point prior to calling this).
   void SetMouseLocationAndFlags(const ui::MouseEvent& event);
 
-  void DispatchEventToTarget(View* target, ui::Event* event);
+  ui::EventDispatchDetails DispatchEventToTarget(View* target,
+                                                 ui::Event* event);
 
   // |view| is the view receiving |event|. This function sends the event to all
   // the Views up the hierarchy that has |notify_enter_exit_on_child_| flag