Touch gestures for System Tray/ IME/ Stylus/ Notifications

ui/views/bubble/tray_bubble_view.h

Index: ui/views/bubble/tray_bubble_view.h
diff --git a/ui/views/bubble/tray_bubble_view.h b/ui/views/bubble/tray_bubble_view.h
index 7fa7034855bea6d7729b536d48776f42aed8e5e6..a5cf5f52e5107a7d6e77e3ac44cd27b6f098283c 100644
--- a/ui/views/bubble/tray_bubble_view.h
+++ b/ui/views/bubble/tray_bubble_view.h
@@ -85,6 +85,11 @@ class VIEWS_EXPORT TrayBubbleView : public BubbleDialogDelegateView,
     // child view was closed).
     virtual void HideBubble(const TrayBubbleView* bubble_view) = 0;
 
+    // Called when a bubble wants to be dragged (e.g. opened system tray bubble
+    // can be dragged downward to close).
+    virtual bool ProcessGestureEventOnBubbleView(ui::GestureEvent* event,
+                                                 View* target);
+
    private:
     DISALLOW_COPY_AND_ASSIGN(Delegate);
   };
@@ -158,6 +163,7 @@ class VIEWS_EXPORT TrayBubbleView : public BubbleDialogDelegateView,
   void OnMouseEntered(const ui::MouseEvent& event) override;
   void OnMouseExited(const ui::MouseEvent& event) override;
   void GetAccessibleNodeData(ui::AXNodeData* node_data) override;
+  void OnGestureEvent(ui::GestureEvent* event) override;
 
   // Overridden from MouseWatcherListener
   void MouseMovedOutOfHost() override;