[Sync] Consolidate DataTypeController methods that post on the backend thread

chrome/browser/sync/glue/non_frontend_data_type_controller.cc

Index: chrome/browser/sync/glue/non_frontend_data_type_controller.cc
diff --git a/chrome/browser/sync/glue/non_frontend_data_type_controller.cc b/chrome/browser/sync/glue/non_frontend_data_type_controller.cc
index 3ae6efee88032c58b05d8b6bf77c838e046b59a7..69ff0ace4d7bf89f55d9e292da5e27450f8e9015 100644
--- a/chrome/browser/sync/glue/non_frontend_data_type_controller.cc
+++ b/chrome/browser/sync/glue/non_frontend_data_type_controller.cc
@@ -278,6 +278,23 @@ void NonFrontendDataTypeController::OnUnrecoverableErrorImpl(
   profile_sync_service_->OnUnrecoverableError(from_here, message);
 }
 
+bool NonFrontendDataTypeController::StartAssociationAsync() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK_EQ(state(), ASSOCIATING);
+  return PostTaskOnBackendThread(
+      FROM_HERE,
+      base::Bind(&NonFrontendDataTypeController::StartAssociation, this));
+}
+
+bool NonFrontendDataTypeController::StopAssociationAsync() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK_EQ(state(), STOPPING);
+  return PostTaskOnBackendThread(
+      FROM_HERE,
+      base::Bind(
+          &NonFrontendDataTypeController::StopAssociation, this));
+}
+
 ProfileSyncComponentsFactory*
     NonFrontendDataTypeController::profile_sync_factory() const {
   return profile_sync_factory_;