Add a flow class to abstract all the details of minting a token for an app.

chrome/common/net/gaia/oauth2_mint_token_fetcher.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_COMMON_NET_GAIA_OAUTH2_MINT_TOKEN_FETCHER_H_
 #define CHROME_COMMON_NET_GAIA_OAUTH2_MINT_TOKEN_FETCHER_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 29 matching lines @@
 // This class can handle one request at a time. To parallelize requests,
 // create multiple instances.
 class OAuth2MintTokenFetcher : public content::URLFetcherDelegate {
  public:
   OAuth2MintTokenFetcher(OAuth2MintTokenConsumer* consumer,
                          net::URLRequestContextGetter* getter,
                          const std::string& source);
   virtual ~OAuth2MintTokenFetcher();
 
   // Start the flow.
-  void Start(const std::string& oauth_login_access_token,
-             const std::string& client_id,
-             const std::vector<std::string>& scopes,
-             const std::string& origin);
+  virtual void Start(const std::string& oauth_login_access_token,
+                     const std::string& client_id,
+                     const std::vector<std::string>& scopes,
+                     const std::string& origin);
 
   void CancelRequest();
 
   // Implementation of content::URLFetcherDelegate
   virtual void OnURLFetchComplete(const content::URLFetcher* source) OVERRIDE;
 
  private:
   enum State {
     INITIAL,
     MINT_TOKEN_STARTED,
@@ skipping 32 matching lines @@
   std::string origin_;
 
   friend class OAuth2MintTokenFetcherTest;
   FRIEND_TEST_ALL_PREFIXES(OAuth2MintTokenFetcherTest,
                            ParseMintTokenResponse);
 
   DISALLOW_COPY_AND_ASSIGN(OAuth2MintTokenFetcher);
 };
 
 #endif  // CHROME_COMMON_NET_GAIA_OAUTH2_MINT_TOKEN_FETCHER_H_