Update the window labels if they change in overview mode.

ash/display/display_controller.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 "ash/display/display_controller.h"
 
 #include <algorithm>
 #include <cmath>
 #include <map>
 
@@ skipping 713 matching lines @@
     const AshWindowTreeHostInitParams& init_params) {
   static int host_count = 0;
   const DisplayInfo& display_info =
       GetDisplayManager()->GetDisplayInfo(display.id());
   AshWindowTreeHostInitParams params_with_bounds(init_params);
   params_with_bounds.initial_bounds = display_info.bounds_in_native();
   AshWindowTreeHost* ash_host = AshWindowTreeHost::Create(params_with_bounds);
   aura::WindowTreeHost* host = ash_host->AsWindowTreeHost();
 
   host->window()->SetName(base::StringPrintf("RootWindow-%d", host_count++));
-  host->window()->set_title(base::UTF8ToUTF16(display_info.name()));
+  host->window()->SetTitle(base::UTF8ToUTF16(display_info.name()));
   host->compositor()->SetBackgroundColor(SK_ColorBLACK);
   // No need to remove our observer observer because the DisplayController
   // outlives the host.
   host->AddObserver(this);
   InitRootWindowSettings(host->window())->display_id = display.id();
   host->InitHost();
 
   window_tree_hosts_[display.id()] = ash_host;
   SetDisplayPropertiesOnHost(ash_host, display);
 
@@ skipping 30 matching lines @@
     std::string name =
         root_windows[i] == primary ? "aura_root_0" : "aura_root_x";
     gfx::AcceleratedWidget xwindow =
         root_windows[i]->GetHost()->GetAcceleratedWidget();
     XStoreName(gfx::GetXDisplay(), xwindow, name.c_str());
   }
 #endif
 }
 
 }  // namespace ash