Add --keyboard-usability-test flag and always show keyboard unless manually hide

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"
 #include "base/lazy_instance.h"
 #include "chrome/browser/chrome_browser_main.h"
 #include "chrome/browser/ui/ash/ash_init.h"
 #include "chrome/browser/ui/ash/ash_util.h"
 #include "chrome/browser/ui/views/ash/tab_scrubber.h"
 #include "chrome/common/chrome_switches.h"
 #include "ui/aura/env.h"
@@ skipping 64 matching lines @@
   if (keyboard::IsKeyboardEnabled())
     keyboard::InitializeKeyboard();
 #endif
 
 #if defined(FILE_MANAGER_EXTENSION)
   ui::SelectFileDialog::SetFactory(new SelectFileDialogExtensionFactory);
 #endif
 }
 
 void ChromeBrowserMainExtraPartsAsh::PostProfileInit() {
-  // Initialize TabScrubber after the Ash Shell has been initialized.
-  if (ash::Shell::HasInstance())
+  // Initialize TabScrubber and activate keyboard after the Ash Shell has been
+  // initialized.
+  if (ash::Shell::HasInstance()) {
     TabScrubber::GetInstance();
+    // Virtual keyboard depends on the default profile.
+    ash::Shell::GetPrimaryRootWindowController()->ActivateKeyboard(
+        ash::Shell::GetInstance()->keyboard_controller());
+  }
 }
 
 void ChromeBrowserMainExtraPartsAsh::PostMainMessageLoopRun() {
   chrome::CloseAsh();
 }