base: Convert the remaining uses of MessageLoop::RunUntilIdle to RunLoop variant.

base/files/file_path_watcher_browsertest.cc

Index: base/files/file_path_watcher_browsertest.cc
diff --git a/base/files/file_path_watcher_browsertest.cc b/base/files/file_path_watcher_browsertest.cc
index e7d1680de539c6e52d8fa1d46f4cf76773276060..4f0cb27cc447b4efc78724e4905a53f4751e7647 100644
--- a/base/files/file_path_watcher_browsertest.cc
+++ b/base/files/file_path_watcher_browsertest.cc
@@ -22,6 +22,7 @@
 #include "base/files/scoped_temp_dir.h"
 #include "base/message_loop.h"
 #include "base/message_loop_proxy.h"
+#include "base/run_loop.h"
 #include "base/stl_util.h"
 #include "base/stringprintf.h"
 #include "base/synchronization/waitable_event.h"
@@ -167,7 +168,7 @@ class FilePathWatcherTest : public testing::Test {
   }
 
   virtual void TearDown() OVERRIDE {
-    loop_.RunUntilIdle();
+    RunLoop().RunUntilIdle();
   }
 
   void DeleteDelegateOnFileThread(TestDelegate* delegate) {