Extract OAuth2AccessTokenFetcher interface.

google_apis/gaia/oauth2_api_call_flow.cc

Index: google_apis/gaia/oauth2_api_call_flow.cc
diff --git a/google_apis/gaia/oauth2_api_call_flow.cc b/google_apis/gaia/oauth2_api_call_flow.cc
index 4c4940d9853e695091f3c35425f732731cf271f4..7f22811180059083cd1d75316e024ec78cbdb3c3 100644
--- a/google_apis/gaia/oauth2_api_call_flow.cc
+++ b/google_apis/gaia/oauth2_api_call_flow.cc
@@ -10,6 +10,7 @@
 #include "base/basictypes.h"
 #include "base/strings/stringprintf.h"
 #include "google_apis/gaia/gaia_urls.h"
+#include "google_apis/gaia/oauth2_access_token_fetcher_impl.h"
 #include "net/base/escape.h"
 #include "net/base/load_flags.h"
 #include "net/http/http_status_code.h"
@@ -109,7 +110,8 @@ void OAuth2ApiCallFlow::BeginMintAccessToken() {
       GaiaUrls::GetInstance()->oauth2_chrome_client_id(),
       GaiaUrls::GetInstance()->oauth2_chrome_client_secret(),
       refresh_token_,
-      scopes_);
+      scopes_,
+      this);
 }
 
 void OAuth2ApiCallFlow::EndMintAccessToken(
@@ -126,7 +128,7 @@ void OAuth2ApiCallFlow::EndMintAccessToken(
 }
 
 OAuth2AccessTokenFetcher* OAuth2ApiCallFlow::CreateAccessTokenFetcher() {
-  return new OAuth2AccessTokenFetcher(this, context_);
+  return new OAuth2AccessTokenFetcherImpl(context_);
 }
 
 void OAuth2ApiCallFlow::OnURLFetchComplete(const net::URLFetcher* source) {