Add ink drop masking to TrayBackgroundView

ui/views/animation/ink_drop_impl.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_VIEWS_ANIMATION_INK_DROP_IMPL_H_
 #define UI_VIEWS_ANIMATION_INK_DROP_IMPL_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 27 matching lines @@
     // ripple is hidden the highlight will be made visible again if the
     // hover/focus settings deem it should be.
     HIDE_ON_RIPPLE,
     // The highlight is made visible when the ripple becomes visible. After the
     // ripple is hidden the highlight will be hidden again if the hover/focus
     // settings deem it should be.
     SHOW_ON_RIPPLE,
   };
 
   // Constructs an ink drop that will attach the ink drop to the given
-  // |ink_drop_host|.
+  // |ink_drop_host|. |layer_size| determines size of the ink drop layer and
+  // should match the host size;
   //
   // By default the highlight will be made visible while |this| is hovered but
   // not focused and the NONE AutoHighlightMode will be used.
-  explicit InkDropImpl(InkDropHost* ink_drop_host);
+  InkDropImpl(InkDropHost* ink_drop_host, const gfx::Size& layer_size);

[bruthig, 2016/11/14 19:09:38]

nit: Rename |layer_size| as |host_size|.  Clients don't need to know what the
size is being used for.

[mohsen, 2016/11/14 20:19:39]

Done.

   ~InkDropImpl() override;
 
   void SetShowHighlightOnHover(bool show_highlight_on_hover);
 
   void SetShowHighlightOnFocus(bool show_highlight_on_focus);
 
   // Auto highlighting is a mechanism to show/hide the highlight based on the
   // visibility of the ripple. See the documentation of the AutoHighlightMode
   // for more info on the different modes.
   //
   // This method is intended as a configuration option to be used after
   // construction. Behavior is undefined if |this| has already handled any
   // InkDrop inherited functions.
   void SetAutoHighlightMode(AutoHighlightMode auto_highlight_mode);
 
   // InkDrop:
+  void UpdateLayerSize(const gfx::Size& layer_size) override;
   InkDropState GetTargetInkDropState() const override;
   void AnimateToState(InkDropState ink_drop_state) override;
   void SnapToActivated() override;
   void SetHovered(bool is_hovered) override;
   void SetFocused(bool is_focused) override;
 
  private:
   friend class InkDropImplTest;
   friend class test::InkDropImplTestApi;
 
@@ skipping 231 matching lines @@
 
   // Used to fail DCHECKS to catch unexpected behavior during tear down.
   bool destroying_;
 
   DISALLOW_COPY_AND_ASSIGN(InkDropImpl);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_ANIMATION_INK_DROP_IMPL_H_