Revert of Add thread checking to RunLoop, deprecate MessageLoopRunner.

chrome/browser/sync_file_system/sync_file_system_service_unittest.cc

Index: chrome/browser/sync_file_system/sync_file_system_service_unittest.cc
diff --git a/chrome/browser/sync_file_system/sync_file_system_service_unittest.cc b/chrome/browser/sync_file_system/sync_file_system_service_unittest.cc
index 84752198d2f82a5775d749e0d9b9c5ea55294420..c4d0035d7aadc7cb1d402e11226285426421adf6 100644
--- a/chrome/browser/sync_file_system/sync_file_system_service_unittest.cc
+++ b/chrome/browser/sync_file_system/sync_file_system_service_unittest.cc
@@ -73,11 +73,12 @@
   run_loop->Quit();
 }
 
-// This is called on IO thread. Posts |callback| to be called on UI thread.
-void VerifyFileError(base::Closure callback,
+// This is called on IO thread.
+void VerifyFileError(base::RunLoop* run_loop,
                      base::File::Error error) {
+  DCHECK(run_loop);
   EXPECT_EQ(base::File::FILE_OK, error);
-  BrowserThread::PostTask(BrowserThread::UI, FROM_HERE, callback);
+  run_loop->Quit();
 }
 
 }  // namespace
@@ -429,7 +430,7 @@
       base::Bind(&CannedSyncableFileSystem::DoCreateFile,
                  base::Unretained(file_system_.get()),
                  kFile, base::Bind(&VerifyFileError,
-                                   verify_file_error_run_loop.QuitClosure())));
+                                   &verify_file_error_run_loop)));
 
   run_loop.Run();