Remove more keyboard usability related code

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 230 matching lines @@
 #endif
   // Reset primary display to make sure that tests don't use
   // stale display info from previous tests.
   primary_display_id = gfx::Display::kInvalidDisplayID;
 }
 
 DisplayController::~DisplayController() {
 }
 
 void DisplayController::Start() {
-  // Created here so that Shell has finished being created. Adds itself
-  // as a ShellObserver.
   Shell::GetScreen()->AddObserver(this);
   Shell::GetInstance()->display_manager()->set_delegate(this);
 }
 
 void DisplayController::Shutdown() {
   // Unset the display manager's delegate here because
   // DisplayManager outlives DisplayController.
   Shell::GetInstance()->display_manager()->set_delegate(NULL);
 
   cursor_window_controller_.reset();
@@ skipping 516 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