Remove experimental code fro grouping notifications from the same source.

ui/message_center/views/toast_contents_view.cc

 // Copyright (c) 2013 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/toast_contents_view.h"
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
@@ skipping 311 matching lines @@
   if (collection_)
     collection_->ClickOnNotificationButton(notification_id, button_index);
 }
 
 void ToastContentsView::ExpandNotification(
     const std::string& notification_id) {
   if (collection_)
     collection_->ExpandNotification(notification_id);
 }
 
-void ToastContentsView::GroupBodyClicked(
-    const std::string& last_notification_id) {
-  // No group views in popup collection.
-  NOTREACHED();
-}
-
-// When clicked on the "N more" button, perform some reasonable action.
-// TODO(dimich): find out what the reasonable action could be.
-void ToastContentsView::ExpandGroup(const NotifierId& notifier_id) {
-  // No group views in popup collection.
-  NOTREACHED();
-}
-
-void ToastContentsView::RemoveGroup(const NotifierId& notifier_id) {
-  // No group views in popup collection.
-  NOTREACHED();
-}
-
 void ToastContentsView::CreateWidget(gfx::NativeView parent) {
   views::Widget::InitParams params(views::Widget::InitParams::TYPE_POPUP);
   params.keep_on_top = true;
   if (parent)
     params.parent = parent;
   else
     params.top_level = true;
   params.opacity = views::Widget::InitParams::TRANSLUCENT_WINDOW;
   params.delegate = this;
   views::Widget* widget = new views::Widget();
@@ skipping 11 matching lines @@
 }
 
 gfx::Rect ToastContentsView::GetClosedToastBounds(gfx::Rect bounds) {
   return gfx::Rect(bounds.x() + bounds.width() - kClosedToastWidth,
                    bounds.y(),
                    kClosedToastWidth,
                    bounds.height());
 }
 
 }  // namespace message_center