Fix processing of mouse events on MacViews.

ui/views/cocoa/bridged_native_widget.h

Index: ui/views/cocoa/bridged_native_widget.h
diff --git a/ui/views/cocoa/bridged_native_widget.h b/ui/views/cocoa/bridged_native_widget.h
index 0bb5fd98c92dc991a4cd65c76565b575f67be260..f26109400542a3fcfe1f6aa0e4ac1e3a4c3bb416 100644
--- a/ui/views/cocoa/bridged_native_widget.h
+++ b/ui/views/cocoa/bridged_native_widget.h
@@ -101,6 +101,8 @@ class VIEWS_EXPORT BridgedNativeWidget
   void ReleaseCapture();
   bool HasCapture();
 
+  void OnMouseEvent(NSEvent* event);
+
   // Start moving the window, pinned to the mouse cursor, and monitor events.
   // Return MOVE_LOOP_SUCCESSFUL on mouse up or MOVE_LOOP_CANCELED on premature
   // termination via EndMoveLoop() or when window is destroyed during the drag.
@@ -263,6 +265,8 @@ class VIEWS_EXPORT BridgedNativeWidget
       base::TimeTicks* timebase, base::TimeDelta* interval) const override;
   void AcceleratedWidgetSwapCompleted() override;
 
+  void SendStoredMouseExitedEventToWidget();
+
   // Overridden from BridgedNativeWidgetOwner:
   NSWindow* GetNSWindow() override;
   gfx::Vector2d GetChildWindowOffset() const override;
@@ -320,6 +324,11 @@ class VIEWS_EXPORT BridgedNativeWidget
 
   AssociatedViews associated_views_;
 
+  // We don't immediately send MouseExited notifications when we're inside of a
+  // drag operation.
+  std::unique_ptr<ui::MouseEvent> pendingExitEvent_;
+  bool mouse_inside_ = false;
+
   DISALLOW_COPY_AND_ASSIGN(BridgedNativeWidget);
 };