Added material design mouse hover feedback support.

ui/views/animation/ink_drop_animation_controller.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_ANIMATION_CONTROLLER_H_
 #define UI_VIEWS_ANIMATION_INK_DROP_ANIMATION_CONTROLLER_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "base/time/time.h"
 #include "ui/compositor/layer_tree_owner.h"
 #include "ui/events/event_handler.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/views/animation/ink_drop_state.h"
 #include "ui/views/views_export.h"
 
 namespace ui {
 class Layer;
 }
 
 namespace views {
 
-// Pure virtual base class that manages an ink drop animation's lifetime and
-// state.
+// Pure virtual base class that manages the lifetime and state of an ink drop
+// animation as well as visual hover state feedback.
 class VIEWS_EXPORT InkDropAnimationController {
  public:
   virtual ~InkDropAnimationController() {}
 
   // Gets the current state of the ink drop.
   virtual InkDropState GetInkDropState() const = 0;
 
   // Animates from the current InkDropState to |ink_drop_state|.
   virtual void AnimateToState(InkDropState ink_drop_state) = 0;
 
+  // Enables or disables the hover state.
+  virtual void SetHovered(bool is_hovered) = 0;
+
+  // Returns true if the hover state is enabled.
+  virtual bool IsHovered() const = 0;
+
   virtual gfx::Size GetInkDropLargeSize() const = 0;
 
   // Sets the different sizes of the ink drop.
   virtual void SetInkDropSize(const gfx::Size& large_size,
                               int large_corner_radius,
                               const gfx::Size& small_size,
                               int small_corner_radius) = 0;
 
   // Sets the |center_point| of the ink drop relative to its parent Layer.
   virtual void SetInkDropCenter(const gfx::Point& center_point) = 0;
 
  protected:
   InkDropAnimationController() {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(InkDropAnimationController);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_ANIMATION_INK_DROP_ANIMATION_CONTROLLER_H_