[Sync] Simplify sync startup behavior.

components/browser_sync/browser/profile_sync_service.h

Index: components/browser_sync/browser/profile_sync_service.h
diff --git a/components/browser_sync/browser/profile_sync_service.h b/components/browser_sync/browser/profile_sync_service.h
index df981bc3e78339f174984afa2b44f2f65a1bddea..bd48e8738f55d00be9560698c9058eb8a2819d94 100644
--- a/components/browser_sync/browser/profile_sync_service.h
+++ b/components/browser_sync/browser/profile_sync_service.h
@@ -165,14 +165,8 @@ class EncryptedData;
 //   up sync at least once on their account. SetSetupInProgress(true) should be
 //   called while the user is actively configuring their account, and then
 //   SetSetupInProgress(false) should be called when configuration is complete.
-//   When SetFirstSetupComplete() == false, but SetSetupInProgress(true) has
-//   been called, then the sync engine knows not to download any user data.
-//
-//   When initial sync is complete, the UI code should call
-//   SetFirstSetupComplete() followed by SetSetupInProgress(false) - this will
-//   tell the sync engine that setup is completed and it can begin downloading
-//   data from the sync server.
-//
+//   Once both these conditions have been met, CanConfigureDataTypes() will
+//   return true and datatype configuration can begin.
 class ProfileSyncService : public sync_driver::SyncService,
                            public sync_driver::SyncFrontend,
                            public sync_driver::SyncPrefObserver,
@@ -508,9 +502,6 @@ class ProfileSyncService : public sync_driver::SyncService,
 
   SigninManagerBase* signin() const;
 
-  // Used by tests.
-  bool auto_start_enabled() const;
-
   SyncErrorController* sync_error_controller() {
     return sync_error_controller_.get();
   }
@@ -782,6 +773,9 @@ class ProfileSyncService : public sync_driver::SyncService,
   // Restarts sync clearing directory in the process.
   void OnClearServerDataDone();
 
+  // True if setup has been completed at least once and is not in progress.
+  bool CanConfigureDataTypes() const;
+
   // This profile's SyncClient, which abstracts away non-Sync dependencies and
   // the Sync API component factory.
   scoped_ptr<sync_driver::SyncClient> sync_client_;