Update WebUILogin Focus for Mash

chrome/browser/chromeos/login/ui/webui_login_view.cc

 // Copyright 2014 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 "chrome/browser/chromeos/login/ui/webui_login_view.h"
 
 #include "ash/common/focus_cycler.h"
 #include "ash/common/system/status_area_widget_delegate.h"
 #include "ash/common/system/tray/system_tray.h"
 #include "ash/common/wm_shell.h"
@@ skipping 337 matching lines @@
   webui_login_->RequestFocus();
 
   // TODO(nkostylev): Use WebContentsObserver::RenderViewCreated to track
   // when RenderView is created.
   GetWebContents()
       ->GetRenderViewHost()
       ->GetWidget()
       ->GetView()
       ->SetBackgroundColor(SK_ColorTRANSPARENT);
 
+  // There is no Shell instance while running in mash.
+  if (chrome::IsRunningInMash())
+    return;
+
   ash::StatusAreaWidgetDelegate* status_area_widget_delegate =
       GetStatusAreaWidgetDelegate();
   DCHECK(status_area_widget_delegate);
   cycle_focus_traversable_.reset(new CycleFocusTraversable(this));
   status_area_focus_traversable_.reset(
       new StatusAreaFocusTraversable(status_area_widget_delegate, this));
   status_area_widget_delegate->set_custom_focus_traversable(
       status_area_focus_traversable_.get());
 }
 
@@ skipping 234 matching lines @@
   if (should_emit_login_prompt_visible_) {
     VLOG(1) << "Login WebUI >> login-prompt-visible";
     chromeos::DBusThreadManager::Get()->GetSessionManagerClient()->
         EmitLoginPromptVisible();
   }
 
   webui_visible_ = true;
 }
 
 }  // namespace chromeos