Move AppWindow to extensions

extensions/browser/app_window/apps_client.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 "apps/ui/apps_client.h"
+#include "extensions/browser/app_window/apps_client.h"
 
 #include "base/basictypes.h"
 
-namespace apps {
+namespace extensions {
 
 namespace {
 
 AppsClient* g_client = NULL;
 
 }  // namespace
 
 AppsClient* AppsClient::Get() {
   return g_client;
 }
 
 void AppsClient::Set(AppsClient* client) {
   // This can happen in unit tests, where the utility thread runs in-process.
   if (g_client)
     return;
 
   g_client = client;
 }
 
-}  // namespace apps
+}  // namespace extensions