Extract OAuth2AccessTokenFetcher interface.

google_apis/gaia/oauth2_token_service.cc

 // 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.
 
 #include "google_apis/gaia/oauth2_token_service.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/memory/weak_ptr.h"
@@ skipping 228 matching lines @@
   waiting_requests_.push_back(waiting_request);
 }
 
 OAuth2TokenService::Fetcher::~Fetcher() {
   // Inform the waiting requests if it has not done so.
   if (waiting_requests_.size())
     InformWaitingRequests();
 }
 
 void OAuth2TokenService::Fetcher::Start() {
-  fetcher_.reset(new OAuth2AccessTokenFetcher(this, getter_.get()));
+  fetcher_.reset(new OAuth2AccessTokenFetcherImpl(getter_.get()));
   fetcher_->Start(client_id_,
                   client_secret_,
                   refresh_token_,
-                  std::vector<std::string>(scopes_.begin(), scopes_.end()));
+                  std::vector<std::string>(scopes_.begin(), scopes_.end()),
+                  this);

[Roger Tawa OOO till Jul 10th, 2014/03/03 21:24:44]

Maybe define a virtual CreateAccessTokenFetcher() method so that you can
override for iOS without forking?

[msarda, 2014/03/04 12:37:13]

I plan to do that in a separate CL. Just to separate the concerns.

   retry_timer_.Stop();
 }
 
 void OAuth2TokenService::Fetcher::OnGetTokenSuccess(
     const std::string& access_token,
     const base::Time& expiration_date) {
   fetcher_.reset();
 
   // Fetch completes.
   error_ = GoogleServiceAuthError::AuthErrorNone();
@@ skipping 533 matching lines @@
     const std::string& account_id,
     const ScopeSet& scopes) const {
   PendingFetcherMap::const_iterator iter = pending_fetchers_.find(
       OAuth2TokenService::RequestParameters(
           client_id,
           account_id,
           scopes));
   return iter == pending_fetchers_.end() ?
              0 : iter->second->GetWaitingRequestCount();
 }