Use ScopedTaskEnvironment instead of MessageLoopForUI in ViewsTestBase.

ui/views/test/views_test_base.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_VIEWS_TEST_VIEWS_TEST_BASE_H_
 #define UI_VIEWS_TEST_VIEWS_TEST_BASE_H_
 
 #include <memory>
 
 #include "base/macros.h"
-#include "base/message_loop/message_loop.h"
+#include "base/test/scoped_task_environment.h"
 #include "build/build_config.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/platform_test.h"
 #include "ui/views/test/scoped_views_test_helper.h"
 #include "ui/views/test/test_views_delegate.h"
 #include "ui/views/widget/widget.h"
 
 #if defined(OS_WIN)
 #include "ui/base/win/scoped_ole_initializer.h"
 #endif
@@ skipping 29 matching lines @@
  protected:
   TestViewsDelegate* test_views_delegate() const {
     return test_helper_->test_views_delegate();
   }
 
   void set_views_delegate(std::unique_ptr<TestViewsDelegate> views_delegate) {
     DCHECK(!setup_called_);
     views_delegate_for_setup_.swap(views_delegate);
   }
 
-  base::MessageLoopForUI* message_loop() { return &message_loop_; }
-
   // Returns a context view. In aura builds, this will be the
   // RootWindow. Everywhere else, NULL.
   gfx::NativeWindow GetContext();
 
  private:
-  base::MessageLoopForUI message_loop_;
+  base::test::ScopedTaskEnvironment scoped_task_environment_;
   std::unique_ptr<TestViewsDelegate> views_delegate_for_setup_;
   std::unique_ptr<ScopedViewsTestHelper> test_helper_;
   bool setup_called_;
   bool teardown_called_;
   bool has_compositing_manager_;
 
 #if defined(OS_WIN)
   ui::ScopedOleInitializer ole_initializer_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(ViewsTestBase);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_TEST_VIEWS_TEST_BASE_H_