Remove use of deprecated MessageLoop methods in ui.

ui/views/widget/native_widget_aura.cc

Index: ui/views/widget/native_widget_aura.cc
diff --git a/ui/views/widget/native_widget_aura.cc b/ui/views/widget/native_widget_aura.cc
index 5fb420fef944fdcddf6b007a588b6b2a8ba691fb..5d1dfc445aee2d21e0b0e149ee891a1e8e6841d6 100644
--- a/ui/views/widget/native_widget_aura.cc
+++ b/ui/views/widget/native_widget_aura.cc
@@ -5,8 +5,11 @@
 #include "ui/views/widget/native_widget_aura.h"
 
 #include "base/bind.h"
+#include "base/location.h"
 #include "base/memory/ptr_util.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_util.h"
+#include "base/threading/thread_task_runner_handle.h"
 #include "build/build_config.h"
 #include "third_party/skia/include/core/SkRegion.h"
 #include "ui/aura/client/aura_constants.h"
@@ -465,10 +468,9 @@ void NativeWidgetAura::Close() {
   }
 
   if (!close_widget_factory_.HasWeakPtrs()) {
-    base::MessageLoop::current()->PostTask(
-        FROM_HERE,
-        base::Bind(&NativeWidgetAura::CloseNow,
-                   close_widget_factory_.GetWeakPtr()));
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(&NativeWidgetAura::CloseNow,
+                              close_widget_factory_.GetWeakPtr()));
   }
 }