Remove the most obvious dead code from message center.

ui/message_center/message_center_tray_unittest.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/message_center_tray.h"
 
 #include "base/strings/utf_string_conversions.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/message_center/message_center.h"
 #include "ui/message_center/notification_types.h"
 
 namespace message_center {
 namespace {
 
 class MockDelegate : public MessageCenterTrayDelegate {
  public:
   MockDelegate()
       : show_popups_success_(true),
         show_message_center_success_(true) {}
   virtual ~MockDelegate() {}
   virtual void OnMessageCenterTrayChanged() OVERRIDE {}
   virtual bool ShowPopups() OVERRIDE {
     return show_message_center_success_;
   }
   virtual void HidePopups() OVERRIDE {}
-  virtual void UpdatePopups() OVERRIDE {}
   virtual bool ShowMessageCenter() OVERRIDE {
     return show_popups_success_;
   }
   virtual void HideMessageCenter() OVERRIDE {}
   virtual bool ShowNotifierSettings() OVERRIDE {
     return false;
   }
 
   bool show_popups_success_;
   bool show_message_center_success_;
@@ skipping 183 matching lines @@
   ASSERT_FALSE(message_center_tray_->popups_visible());
   ASSERT_FALSE(message_center_tray_->message_center_visible());
 
   message_center_tray_->HidePopupBubble();
 
   ASSERT_FALSE(message_center_tray_->popups_visible());
   ASSERT_FALSE(message_center_tray_->message_center_visible());
 }
 
 }  // namespace message_center