Fix some migration-related bugs

chrome/browser/sync/profile_sync_service.cc

Index: chrome/browser/sync/profile_sync_service.cc
diff --git a/chrome/browser/sync/profile_sync_service.cc b/chrome/browser/sync/profile_sync_service.cc
index 27e3e56c5779796467e6867e98bb9a811fe4d154..c687fc537524bb3121cf6610feaa0249e969f09f 100644
--- a/chrome/browser/sync/profile_sync_service.cc
+++ b/chrome/browser/sync/profile_sync_service.cc
@@ -1457,10 +1457,15 @@ void ProfileSyncService::Observe(int type,
         backend_->EnableEncryptEverything();
       NotifyObservers();
 
-      // In the old world, this would be a no-op.  With new syncer thread,
-      // this is the point where it is safe to switch from config-mode to
-      // normal operation.
-      backend_->StartSyncingWithServer();
+      if (migrator_.get() &&
+          migrator_->state() != browser_sync::BackendMigrator::IDLE) {
+        // Migration in progress.  Let the migrator know we just finished
+        // configuring something.  It will be up to the migrator to call
+        // StartSyncingWithServer() if migration is now finished.
+        migrator_->OnConfigureDone(*result);
+      } else {
+        StartSyncingWithServer();
+      }
 
       break;
     }
@@ -1543,6 +1548,11 @@ void ProfileSyncService::Observe(int type,
   }
 }
 
+void ProfileSyncService::StartSyncingWithServer() {
+  if (backend_.get())
+    backend_->StartSyncingWithServer();
+}
+
 void ProfileSyncService::AddObserver(Observer* observer) {
   observers_.AddObserver(observer);
 }