Avoid to call KeyboardController::ResetInstance twice

ash/shell.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/shell.h"
 
 #include <algorithm>
 #include <string>
 #include <utility>
 
@@ skipping 650 matching lines @@
   // Balances the Install() in Initialize().
   views::FocusManagerFactory::Install(nullptr);
 
   wm_shell_->Shutdown();
   // Depends on |focus_controller_|, so must be destroyed before.
   window_tree_host_manager_.reset();
   focus_controller_->RemoveObserver(this);
   focus_controller_.reset();
   screen_position_controller_.reset();
 
-  keyboard::KeyboardController::ResetInstance(nullptr);
-
   display_color_manager_.reset();
   if (display_change_observer_)
     display_configurator_->RemoveObserver(display_change_observer_.get());
   if (display_error_observer_)
     display_configurator_->RemoveObserver(display_error_observer_.get());
   if (projecting_observer_) {
     display_configurator_->RemoveObserver(projecting_observer_.get());
     RemoveShellObserver(projecting_observer_.get());
   }
   display_change_observer_.reset();
@@ skipping 420 matching lines @@
 void Shell::OnWindowActivated(
     aura::client::ActivationChangeObserver::ActivationReason reason,
     aura::Window* gained_active,
     aura::Window* lost_active) {
   WmWindow* gained_active_wm = WmWindow::Get(gained_active);
   if (gained_active_wm)
     root_window_for_new_windows_ = gained_active_wm->GetRootWindow();
 }
 
 }  // namespace ash