Touch gestures for System Tray/ IME/ Stylus/ Notifications

ash/system/tray/system_tray.h

Index: ash/system/tray/system_tray.h
diff --git a/ash/system/tray/system_tray.h b/ash/system/tray/system_tray.h
index fe8a0fdd31ce963155313cde514041c6370d8e13..568b7c12dc97f48c72dd862ed1db1ed4ef94334c 100644
--- a/ash/system/tray/system_tray.h
+++ b/ash/system/tray/system_tray.h
@@ -142,6 +142,8 @@ class ASH_EXPORT SystemTray : public TrayBackgroundView,
   base::string16 GetAccessibleNameForBubble() override;
   bool ShouldEnableExtraKeyboardAccessibility() override;
   void HideBubble(const views::TrayBubbleView* bubble_view) override;
+  bool ProcessGestureEventOnBubbleView(ui::GestureEvent* event,
+                                       View* target) override;
 
   ScreenTrayItem* GetScreenShareItem() { return screen_share_tray_item_; }
   ScreenTrayItem* GetScreenCaptureItem() { return screen_capture_tray_item_; }
@@ -232,6 +234,9 @@ class ASH_EXPORT SystemTray : public TrayBackgroundView,
   // tray bubble, false otherwise.
   bool is_in_drag_ = false;
 
+  // The target view that the sequence of scroll events happened on.
+  View* target_view_;
+
   // The web notification tray view that appears adjacent to this view.
   WebNotificationTray* web_notification_tray_ = nullptr;