Add a full screen virtual keyboard to virtual keyboard root window

chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.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 "chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.h"
 
 #include "ash/root_window_controller.h"
 #include "ash/session_state_delegate.h"
 #include "ash/shell.h"
 #include "base/command_line.h"
@@ skipping 77 matching lines @@
 #endif
 }
 
 void ChromeBrowserMainExtraPartsAsh::PostProfileInit() {
   if (!ash::Shell::HasInstance())
     return;
 
   // Initialize TabScrubber after the Ash Shell has been initialized.
   TabScrubber::GetInstance();
   // Activate virtual keyboard after profile is initialized. It depends on the
-  // default profile.
-  ash::Shell::GetPrimaryRootWindowController()->ActivateKeyboard(
-      ash::Shell::GetInstance()->keyboard_controller());
+  // default profile. If keyboard usability test flag is set, defer the
+  // activation to UpdateWindow() in virtual_keyboard_window_controller.cc.
+  if (!keyboard::IsKeyboardUsabilityTestEnabled()) {
+    ash::Shell::GetPrimaryRootWindowController()->ActivateKeyboard(
+        ash::Shell::GetInstance()->keyboard_controller());
+  }
 }
 
 void ChromeBrowserMainExtraPartsAsh::PostMainMessageLoopRun() {
   chrome::CloseAsh();
 }