Enhanced the InkDropRippleImpl to create/destroy InkDropAnimations as needed.

ui/views/views.gyp

 # Copyright (c) 2012 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.
 {
   'variables': {
     'chromium_code': 1,
     # Sources lists shared with GN build.
     'views_sources': [
       'accessibility/native_view_accessibility.cc',
       'accessibility/native_view_accessibility.h',
       'accessibility/native_view_accessibility_win.cc',
       'accessibility/native_view_accessibility_win.h',
       'accessible_pane_view.cc',
       'accessible_pane_view.h',
       'animation/bounds_animator.cc',
       'animation/bounds_animator.h',
       'animation/ink_drop_animation.cc',
       'animation/ink_drop_animation.h',
       'animation/ink_drop_animation_controller.h',
       'animation/ink_drop_animation_controller_factory.cc',
       'animation/ink_drop_animation_controller_factory.h',
       'animation/ink_drop_animation_controller_impl.cc',
       'animation/ink_drop_animation_controller_impl.h',
+      'animation/ink_drop_animation_observer.cc',
+      'animation/ink_drop_animation_observer.h',
       'animation/ink_drop_host.h',
+      'animation/ink_drop_state.cc',
       'animation/ink_drop_state.h',
       'animation/scroll_animator.cc',
       'animation/scroll_animator.h',
       'background.cc',
       'background.h',
       'border.cc',
       'border.h',
       'bubble/bubble_border.cc',
       'bubble/bubble_border.h',
       'bubble/bubble_delegate.cc',
@@ skipping 917 matching lines @@
                 '../aura/aura.gyp:aura',
                 '../wm/wm.gyp:wm',
               ],
             }],
           ],
         },  # target_name: macviews_interactive_ui_tests
       ],  # targets
     }],
   ],  # conditions
 }