mash: Break ash system tray dependencies on ash::ShelfWidget

ash/mus/bridge/wm_shelf_mus.h

Index: ash/mus/bridge/wm_shelf_mus.h
diff --git a/ash/mus/bridge/wm_shelf_mus.h b/ash/mus/bridge/wm_shelf_mus.h
index 0e1ff4bb6c8db38c07d77a94d4fe58a987244e56..329f5690c99fda66de73b936a84ad2e26bba8368 100644
--- a/ash/mus/bridge/wm_shelf_mus.h
+++ b/ash/mus/bridge/wm_shelf_mus.h
@@ -31,12 +31,18 @@ class WmShelfMus : public WmShelf {
   ShelfAutoHideBehavior GetAutoHideBehavior() const override;
   void SetAutoHideBehavior(ShelfAutoHideBehavior behavior) override;
   ShelfAutoHideState GetAutoHideState() const override;
+  void UpdateAutoHideState() override;
   ShelfBackgroundType GetBackgroundType() const override;
+  bool IsDimmed() const override;
+  bool IsVisible() const override;
   void UpdateVisibilityState() override;
   ShelfVisibilityState GetVisibilityState() const override;
+  gfx::Rect GetIdealBounds() override;
   gfx::Rect GetUserWorkAreaBounds() const override;
   void UpdateIconPositionForWindow(WmWindow* window) override;
   gfx::Rect GetScreenBoundsOfItemIconForWindow(WmWindow* window) override;
+  void UpdateAutoHideForMouseEvent(ui::MouseEvent* event) override;
+  void UpdateAutoHideForGestureEvent(ui::GestureEvent* event) override;
   void AddObserver(WmShelfObserver* observer) override;
   void RemoveObserver(WmShelfObserver* observer) override;