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

ash/aura/wm_shelf_aura.h

Index: ash/aura/wm_shelf_aura.h
diff --git a/ash/aura/wm_shelf_aura.h b/ash/aura/wm_shelf_aura.h
index d796f46586e30856251750833117fe080c3e8ba5..33bf58cc83356081fca678660659c32099aa1459 100644
--- a/ash/aura/wm_shelf_aura.h
+++ b/ash/aura/wm_shelf_aura.h
@@ -44,12 +44,18 @@ class ASH_EXPORT WmShelfAura : 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;