arc: Implement retry logic for transient errors

chrome/browser/chromeos/arc/arc_auth_context.h

Index: chrome/browser/chromeos/arc/arc_auth_context.h
diff --git a/chrome/browser/chromeos/arc/arc_auth_context.h b/chrome/browser/chromeos/arc/arc_auth_context.h
index c0aee9cedc78a9d7766de409d19575c78891eeba..e150255e932d39c7ac5b43412349b74e9f9d9f38 100644
--- a/chrome/browser/chromeos/arc/arc_auth_context.h
+++ b/chrome/browser/chromeos/arc/arc_auth_context.h
@@ -65,6 +65,7 @@ class ArcAuthContext : public UbertokenConsumer,
 
   void StartFetchers();
   void ResetFetchers();
+  void OnFetcherError(const GoogleServiceAuthError& error);
 
   // Unowned pointer.
   ProfileOAuth2TokenService* token_service_;
@@ -78,7 +79,12 @@ class ArcAuthContext : public UbertokenConsumer,
   PrepareCallback callback_;
   bool context_prepared_ = false;
 
+  // Contains number of retry attempts to prepare context. 0 means no retry
+  // has occurred.
+  int retry_attempt_count_ = 0;
+
   base::OneShotTimer refresh_token_timeout_;
+  base::OneShotTimer retry_timeout_;
   std::unique_ptr<GaiaAuthFetcher> merger_fetcher_;
   std::unique_ptr<UbertokenFetcher> ubertoken_fetcher_;