Add ink drop ripple to shelf overflow button

ash/common/shelf/overflow_bubble.h

Index: ash/common/shelf/overflow_bubble.h
diff --git a/ash/common/shelf/overflow_bubble.h b/ash/common/shelf/overflow_bubble.h
index b806a55547eb3894e90b63cb774920e082db0fff..6f000926d01b4cca76147d16e0c6403cf7fd36ab 100644
--- a/ash/common/shelf/overflow_bubble.h
+++ b/ash/common/shelf/overflow_bubble.h
@@ -19,6 +19,7 @@ class View;
 
 namespace ash {
 class OverflowBubbleView;
+class OverflowButton;
 class ShelfView;
 class WmShelf;
 
@@ -31,16 +32,13 @@ class OverflowBubble : public views::PointerWatcher,
   explicit OverflowBubble(WmShelf* wm_shelf);
   ~OverflowBubble() override;
 
-  // Shows an bubble pointing to |anchor| with |shelf_view| as its content.
+  // Shows an bubble pointing to |button| with |shelf_view| as its content.
   // This |shelf_view| is different than the main shelf's view and only contains
   // the overflow items.
-  void Show(views::View* anchor, ShelfView* shelf_view);
+  void Show(OverflowButton* button, ShelfView* shelf_view);
 
   void Hide();
 
-  // Hides the bubble and schedules paint for overflow button.
-  void HideBubbleAndRefreshButton();
-
   bool IsShowing() const { return !!bubble_; }
   ShelfView* shelf_view() { return shelf_view_; }
   OverflowBubbleView* bubble_view() { return bubble_; }
@@ -58,7 +56,7 @@ class OverflowBubble : public views::PointerWatcher,
 
   WmShelf* wm_shelf_;
   OverflowBubbleView* bubble_;  // Owned by views hierarchy.
-  views::View* anchor_;         // Owned by ShelfView.
+  OverflowButton* button_;      // Owned by ShelfView.
 
   // ShelfView containing the overflow items. Owned by |bubble_|.
   ShelfView* shelf_view_;