Moving oauth code from host to base to allow code sharing between host and client.

remoting/base/mock_oauth_client.h

 // Copyright 2015 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 REMOTING_HOST_SETUP_MOCK_OAUTH_CLIENT_H_
-#define REMOTING_HOST_SETUP_MOCK_OAUTH_CLIENT_H_
+#ifndef REMOTING_BASE_MOCK_OAUTH_CLIENT_H_
+#define REMOTING_BASE_MOCK_OAUTH_CLIENT_H_
 
-#include "remoting/host/setup/oauth_client.h"
+#include "remoting/base/oauth_client.h"
 
 namespace remoting {
 
 class MockOAuthClient : public OAuthClient {
  public:
   MockOAuthClient(const std::string& user_email,
                   const std::string& refresh_token);
 
   ~MockOAuthClient() override;
 
   void GetCredentialsFromAuthCode(
       const gaia::OAuthClientInfo& oauth_client_info,
       const std::string& auth_code,
       bool need_user_email,
       CompletionCallback on_done) override;
 
  private:
   std::string user_email_;
   std::string refresh_token_;
 };
 
 }  // namespace remoting
 
-#endif  // REMOTING_HOST_SETUP_MOCK_OAUTH_CLIENT_H_
+#endif  // REMOTING_BASE_MOCK_OAUTH_CLIENT_H_