Add MD ink drop ripple to app list button

ui/views/controls/button/custom_button.cc

 // 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.
 
 #include "ui/views/controls/button/custom_button.h"
 
 #include "ui/accessibility/ax_view_state.h"
 #include "ui/base/material_design/material_design_controller.h"
 #include "ui/events/event.h"
 #include "ui/events/event_utils.h"
@@ skipping 145 matching lines @@
     NotifyClick(event);
     // NOTE: We may be deleted at this point (by the listener's notification
     // handler).
   }
   return true;
 }
 
 bool CustomButton::OnMouseDragged(const ui::MouseEvent& event) {
   if (state_ != STATE_DISABLED) {
     const bool should_enter_pushed = ShouldEnterPushedState(event);
+    const bool should_show_pending =
+        should_enter_pushed && notify_action_ == NOTIFY_ON_RELEASE && !InDrag();
     if (HitTestPoint(event.location())) {
       SetState(should_enter_pushed ? STATE_PRESSED : STATE_HOVERED);
-      if (!InDrag() && should_enter_pushed &&
+      if (should_show_pending &&
           ink_drop()->GetTargetInkDropState() == views::InkDropState::HIDDEN) {
         AnimateInkDrop(views::InkDropState::ACTION_PENDING, &event);
       }
     } else {
       SetState(STATE_NORMAL);
-      if (!InDrag() && should_enter_pushed &&
+      if (should_show_pending &&
           ink_drop()->GetTargetInkDropState() ==
               views::InkDropState::ACTION_PENDING) {
         AnimateInkDrop(views::InkDropState::HIDDEN, &event);
       }
     }
   }
   return true;
 }
 
 void CustomButton::OnMouseReleased(const ui::MouseEvent& event) {
@@ skipping 282 matching lines @@
   Button::NotifyClick(event);
 }
 
 void CustomButton::OnClickCanceled(const ui::Event& event) {
   AnimateInkDrop(views::InkDropState::HIDDEN,
                  ui::LocatedEvent::FromIfValid(&event));
   Button::OnClickCanceled(event);
 }
 
 }  // namespace views