sync: preliminary support for deferred SyncBackendHost initialization

chrome/browser/sync/profile_sync_service.h

Index: chrome/browser/sync/profile_sync_service.h
diff --git a/chrome/browser/sync/profile_sync_service.h b/chrome/browser/sync/profile_sync_service.h
index 8eb22b6a93da1fc151c36344185dae6bca5d57be..5bb31bc1b204d862fe467b8e748f6201be88a36c 100644
--- a/chrome/browser/sync/profile_sync_service.h
+++ b/chrome/browser/sync/profile_sync_service.h
@@ -381,6 +381,7 @@ class ProfileSyncService : public ProfileSyncServiceBase,
 
   // Returns a user-friendly string form of last synced time (in minutes).
   virtual string16 GetLastSyncedTimeString() const;
+  std::string GetBackendInitializationStateString() const;

[Nicolas Zea, 2013/02/19 19:01:06]

Newline above this and add comment about what this describes.

[tim (not reviewing), 2013/02/21 03:50:54]

Done.

 
   // Returns true if startup is suppressed (i.e. user has stopped syncing via
   // the google dashboard).
@@ -617,8 +618,6 @@ class ProfileSyncService : public ProfileSyncServiceBase,
   // Helper to install and configure a data type manager.
   void ConfigureDataTypeManager();
 
-  // Starts up the backend sync components.
-  virtual void StartUp();
   // Shuts down the backend sync components.
   // |sync_disabled| indicates if syncing is being disabled or not.
   void ShutdownImpl(bool sync_disabled);
@@ -718,6 +717,15 @@ class ProfileSyncService : public ProfileSyncServiceBase,
 
   void ClearUnrecoverableError();
 
+  enum StartUpDeferred {

[Nicolas Zea, 2013/02/19 19:01:06]

nit: StartUpPolicy seems like a better name for this

[tim (not reviewing), 2013/02/21 03:50:54]

Went with StartUpDeferredOption, because 'start up policy' sounds pretty
ambiguous (i.e I could see us adding a param to StartUp down the road and
'policy' making sense for that too).  Let me know if this is OK with you.

+    STARTUP_DEFER_BACKEND,
+    STARTUP_IMMEDIATE
+  };
+  void StartUp(StartUpDeferred deferred);
+
+  // Starts up the backend sync components.
+  void StartUpSlowBackendComponents();
+
   // About-flags experiment names for datatypes that aren't enabled by default
   // yet.
   static std::string GetExperimentNameForDataType(