Add a full screen virtual keyboard to virtual keyboard root window

ash/shell/keyboard_controller_proxy_stub.cc

Index: ash/shell/keyboard_controller_proxy_stub.cc
diff --git a/ash/keyboard_controller_proxy_stub.cc b/ash/shell/keyboard_controller_proxy_stub.cc
similarity index 78%
rename from ash/keyboard_controller_proxy_stub.cc
rename to ash/shell/keyboard_controller_proxy_stub.cc
index 6db733c576012de46e3c3d71d257a290216eeada..700c834365f02671dff6509ae3871363f809e74c 100644
--- a/ash/keyboard_controller_proxy_stub.cc
+++ b/ash/shell/keyboard_controller_proxy_stub.cc
@@ -2,10 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "ash/keyboard_controller_proxy_stub.h"
+#include "ash/shell/keyboard_controller_proxy_stub.h"
 
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
+#include "ui/aura/window.h"
 #include "ui/views/corewm/input_method_event_filter.h"
 
 using namespace content;
@@ -18,6 +19,12 @@ KeyboardControllerProxyStub::KeyboardControllerProxyStub() {
 KeyboardControllerProxyStub::~KeyboardControllerProxyStub() {
 }
 
+aura::Window* KeyboardControllerProxyStub::GetKeyboardWindow() {
+  aura::Window* window = new aura::Window(&delegate_);
+  window->Init(ui::LAYER_NOT_DRAWN);
+  return window;
+}
+
 BrowserContext* KeyboardControllerProxyStub::GetBrowserContext() {
   return Shell::GetInstance()->delegate()->GetCurrentBrowserContext();
 }