sync: centralize sync startup decisions in TryStart.

chrome/browser/signin/token_service.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.
 //
 // The TokenService will supply authentication tokens for any service that
 // needs it, such as sync. Whenever the user logs in, a controller watching
 // the token service is expected either to call ClientLogin to derive a new
 // SID and LSID, or to use GAIA OAuth requests to derive an OAuth1 access
 // token for the OAuthLogin scope.  Whenever such credentials are available,
 // the TokenService should be updated with new credentials.  The controller
@@ skipping 126 matching lines @@
   // Terminate any running requests and reset the TokenService to a clean
   // slate. Resets in memory structures. Does not modify the DB.
   // When this is done, no tokens will be left in memory and no
   // user credentials will be left. Useful if a user is logging out.
   // Initialize doesn't need to be called again but UpdateCredentials does.
   void ResetCredentialsInMemory();
 
   // Async load all tokens for services we know of from the DB.
   // You should do this at startup. Optionally you can do it again
   // after you reset in memory credentials.
-  void LoadTokensFromDB();
+  virtual void LoadTokensFromDB();
 
   // Clear all DB stored tokens for the current profile. Tokens may still be
   // available in memory. If a DB load is pending it may still be serviced.
   void EraseTokensFromDB();
 
   // Returns true if tokens have been loaded from the DB. Set when
   // LoadTokensFromDB() completes, unset when ResetCredentialsInMemory() is
   // called.
   bool TokensLoadedFromDB() const;
 
@@ skipping 32 matching lines @@
       const GoogleServiceAuthError& error) OVERRIDE;
   virtual void OnClientOAuthSuccess(const ClientOAuthResult& result) OVERRIDE;
   virtual void OnClientOAuthFailure(
       const GoogleServiceAuthError& error) OVERRIDE;
 
   // WebDataServiceConsumer implementation.
   virtual void OnWebDataServiceRequestDone(
       WebDataService::Handle h,
       const WDTypedResult* result) OVERRIDE;
 
+ protected:
+  void set_tokens_loaded(bool loaded) {
+    tokens_loaded_ = loaded;
+  }
+
  private:
 
   // Gets the list of all service names for which tokens will be retrieved.
   // This method is meant only for tests.
   static void GetServiceNamesForTesting(std::vector<std::string>* names);
 
   void FireCredentialsUpdatedNotification(const std::string& lsid,
                                           const std::string& sid);
 
   void FireTokenAvailableNotification(const std::string& service,
@@ skipping 45 matching lines @@
 
   friend class TokenServiceTest;
   FRIEND_TEST_ALL_PREFIXES(TokenServiceTest, LoadTokensIntoMemoryBasic);
   FRIEND_TEST_ALL_PREFIXES(TokenServiceTest, LoadTokensIntoMemoryAdvanced);
   FRIEND_TEST_ALL_PREFIXES(TokenServiceTest, FullIntegrationNewServicesAdded);
 
   DISALLOW_COPY_AND_ASSIGN(TokenService);
 };
 
 #endif  // CHROME_BROWSER_SIGNIN_TOKEN_SERVICE_H_