Remove calls to deprecated MessageLoop methods in components.

components/sync_driver/glue/sync_backend_registrar_unittest.cc

Index: components/sync_driver/glue/sync_backend_registrar_unittest.cc
diff --git a/components/sync_driver/glue/sync_backend_registrar_unittest.cc b/components/sync_driver/glue/sync_backend_registrar_unittest.cc
index e004543daa97308de17f0423a1b561ee21c4026a..89ddfc85b09d0c1f06b992692868fb309ed2f6a2 100644
--- a/components/sync_driver/glue/sync_backend_registrar_unittest.cc
+++ b/components/sync_driver/glue/sync_backend_registrar_unittest.cc
@@ -120,7 +120,7 @@ class SyncBackendRegistrarTest : public testing::Test {
         FROM_HERE, base::Bind(&SyncBackendRegistrar::Shutdown,
                               base::Unretained(registrar_.release())));
     sync_thread_->WaitUntilThreadStarted();
-    sync_thread_->message_loop()->RunUntilIdle();
+    base::RunLoop().RunUntilIdle();
   }
 
   void ExpectRoutingInfo(
@@ -455,7 +455,7 @@ TEST_F(SyncBackendRegistrarShutdownTest, BlockingShutdown) {
 
   // The test verifies that the sync thread doesn't block because
   // of the blocked DB thread and can finish the shutdown.
-  sync_thread->message_loop()->RunUntilIdle();
+  base::RunLoop().RunUntilIdle();
 
   db_thread_lock_.Release();