[Notifications] Fix swipe to close for ARC notifications.

ui/message_center/views/custom_notification_view.cc

 // Copyright 2016 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/message_center/views/custom_notification_view.h"
 
 #include <algorithm>
 
 #include "ui/base/ime/input_method.h"
 #include "ui/base/ime/text_input_client.h"
@@ skipping 66 matching lines @@
 
 const char* CustomNotificationView::GetClassName() const {
   return kViewClassName;
 }
 
 void CustomNotificationView::UpdateControlButtonsVisibility() {
   if (contents_view_delegate_)
     contents_view_delegate_->UpdateControlButtonsVisibility();
 }
 
+void CustomNotificationView::OnSlideChanged() {
+  if (contents_view_delegate_)
+    contents_view_delegate_->OnSlideChanged();
+}
+
 gfx::Size CustomNotificationView::GetPreferredSize() const {
   const gfx::Insets insets = GetInsets();
   const int contents_width = kNotificationWidth - insets.width();
   const int contents_height = contents_view_->GetHeightForWidth(contents_width);
   return gfx::Size(kNotificationWidth, contents_height + insets.height());
 }
 
 void CustomNotificationView::Layout() {
   MessageView::Layout();
 
@@ skipping 54 matching lines @@
 }
 
 bool CustomNotificationView::HandleAccessibleAction(
     const ui::AXActionData& action) {
   if (contents_view_)
     return contents_view_->HandleAccessibleAction(action);
   return false;
 }
 
 }  // namespace message_center