Moved apps metro code from apps to chrome/browser/apps.

apps/apps_client.h

 // Copyright 2013 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.
 
 #ifndef APPS_APPS_CLIENT_H_
 #define APPS_APPS_CLIENT_H_
 
 #include <vector>
 
 namespace content {
 class BrowserContext;
 }
 
+namespace extensions {
+class Extension;
+}
+
 namespace apps {
 
 // Sets up global state for the apps system. Should be Set() once in each
 // process. This should be implemented by the client of the apps system.
 class AppsClient {
  public:
   // Get all loaded browser contexts.
   virtual std::vector<content::BrowserContext*> GetLoadedBrowserContexts() = 0;
 
+  // Do any pre app launch checks. Returns true if the app launch should proceed
+  // or false if the launch should be prevented.
+  virtual bool CheckAppLaunch(content::BrowserContext* context,
+                              const extensions::Extension* extension) = 0;
+
   // Return the apps client.
   static AppsClient* Get();
 
   // Initialize the apps system with this apps client.
   static void Set(AppsClient* client);
 };
 
 }  // namespace apps
 
 #endif  // APPS_APPS_CLIENT_H_