Add ink drop ripple to overview mode button

ash/common/system/tray/tray_background_view.h

Index: ash/common/system/tray/tray_background_view.h
diff --git a/ash/common/system/tray/tray_background_view.h b/ash/common/system/tray/tray_background_view.h
index b642ca692d688ae12e4acb071bea3796d18a2891..4197403af2d6682e1e1f96255a1e86dcf70287a2 100644
--- a/ash/common/system/tray/tray_background_view.h
+++ b/ash/common/system/tray/tray_background_view.h
@@ -78,8 +78,9 @@ class ASH_EXPORT TrayBackgroundView : public ActionableView,
   void OnPaint(gfx::Canvas* canvas) override;
 
   // ActionableView:
-  bool PerformAction(const ui::Event& event) override;
-  gfx::Rect GetFocusBounds() override;
+  std::unique_ptr<views::InkDropRipple> CreateInkDropRipple() const override;
+  std::unique_ptr<views::InkDropHighlight> CreateInkDropHighlight()
+      const override;
   void OnGestureEvent(ui::GestureEvent* event) override;
 
   // Called whenever the shelf alignment changes.
@@ -105,8 +106,10 @@ class ASH_EXPORT TrayBackgroundView : public ActionableView,
   // Sets |contents| as a child.
   void SetContents(views::View* contents);
 
-  // Creates and sets contents background to |background_|.
-  void SetContentsBackground();
+  // Creates and sets contents background to |background_|. |draws_active|
+  // determines if the view's background should be drawn as active when the view
+  // is in the active state.
+  void SetContentsBackground(bool draws_active);
 
   // Returns the anchor rect for the bubble.
   gfx::Rect GetBubbleAnchorRect(
@@ -117,11 +120,8 @@ class ASH_EXPORT TrayBackgroundView : public ActionableView,
   // Returns the bubble anchor alignment based on |shelf_alignment_|.
   views::TrayBubbleView::AnchorAlignment GetAnchorAlignment() const;
 
-  // Forces the background to be drawn active if set to true.
-  void SetDrawBackgroundAsActive(bool visible);
-
-  // Returns true when the the background was overridden to be drawn as active.
-  bool draw_background_as_active() const { return draw_background_as_active_; }
+  void SetIsActive(bool is_active);
+  bool is_active() const { return is_active_; }
 
   TrayContainer* tray_container() const { return tray_container_; }
   ShelfAlignment shelf_alignment() const { return shelf_alignment_; }
@@ -137,6 +137,14 @@ class ASH_EXPORT TrayBackgroundView : public ActionableView,
   // Updates the visibility of this tray's separator.
   void SetSeparatorVisibility(bool is_show);
 
+ protected:
+  // ActionableView:
+  bool ShouldEnterPushedState(const ui::Event& event) override;
+  bool PerformAction(const ui::Event& event) override;
+  void HandlePerformActionResult(bool action_performed,
+                                 const ui::Event& event) override;
+  gfx::Rect GetFocusBounds() override;
+
  private:
   class TrayWidgetObserver;
 
@@ -161,9 +169,9 @@ class ASH_EXPORT TrayBackgroundView : public ActionableView,
   // Owned by the view passed to SetContents().
   TrayBackground* background_;
 
-  // This variable stores the activation override which will tint the background
-  // differently if set to true.
-  bool draw_background_as_active_;
+  // Determines if the view is active. This changes how the background is drawn
+  // in non-MD version and how the ink drop ripples behave in MD version.
+  bool is_active_;
 
   // Visibility of this tray's separator which is a line of 1x32px and 4px to
   // right of tray.