Move UserContext to its own file

chrome/browser/chromeos/login/user_flow.h

 // 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_LOGIN_USER_FLOW_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_USER_FLOW_H_
 
 #include "base/compiler_specific.h"
 #include "chrome/browser/chromeos/login/auth/login_status_consumer.h"
 #include "chrome/browser/chromeos/login/users/user.h"
 #include "chrome/browser/profiles/profile.h"
 
 namespace chromeos {
 
+class UserContext;
+
 class LoginDisplayHost;
 // Defines possible variants of user flow upon logging in.
 // See UserManager::SetUserFlow for usage contract.
 class UserFlow {
  public:
   UserFlow();
   virtual ~UserFlow() = 0;
   // Indicates if screen locking should be enabled or disabled for a flow.
   virtual bool CanLockScreen() = 0;
   virtual bool ShouldShowSettings() = 0;
@@ skipping 49 matching lines @@
     return user_id_;
   }
 
  private:
   std::string user_id_;
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USER_FLOW_H_