mash: Fix shelf window property use in Chrome.

ui/aura/window.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/aura/window.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <utility>
@@ skipping 174 matching lines @@
   type_ = type;
 }
 
 void Window::SetName(const std::string& name) {
   name_ = name;
   if (layer())
     UpdateLayerName();
 }
 
 void Window::SetTitle(const base::string16& title) {
+  if (title == title_)
+    return;
   title_ = title;
   FOR_EACH_OBSERVER(WindowObserver,
                     observers_,
                     OnWindowTitleChanged(this));
 }
 
 void Window::SetTransparent(bool transparent) {
   transparent_ = transparent;
   if (layer())
     layer()->SetFillsBoundsOpaquely(!transparent_);
@@ skipping 911 matching lines @@
     layer_name = "Unnamed Window";
 
   if (id_ != -1)
     layer_name += " " + base::IntToString(id_);
 
   layer()->set_name(layer_name);
 #endif
 }
 
 }  // namespace aura