Use ScopedTaskEnvironment instead of MessageLoopForUI in ui tests.

ui/views/animation/bounds_animator_unittest.cc

 // 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.
 
 #include "ui/views/animation/bounds_animator.h"
 
 #include "base/macros.h"
 #include "base/run_loop.h"
+#include "base/test/scoped_task_environment.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/gfx/animation/slide_animation.h"
 #include "ui/gfx/animation/test_animation_delegate.h"
 #include "ui/views/view.h"
 
 using gfx::Animation;
 using gfx::SlideAnimation;
 using gfx::TestAnimationDelegate;
 
 namespace views {
@@ skipping 65 matching lines @@
  private:
   gfx::Rect dirty_rect_;
 
   DISALLOW_COPY_AND_ASSIGN(TestView);
 };
 
 }  // namespace
 
 class BoundsAnimatorTest : public testing::Test {
  public:
-  BoundsAnimatorTest() : child_(new TestView()), animator_(&parent_) {
+  BoundsAnimatorTest()
+      : scoped_task_environment_(
+            base::test::ScopedTaskEnvironment::MainThreadType::UI),
+        child_(new TestView()),
+        animator_(&parent_) {
     parent_.AddChildView(child_);
   }
 
   TestView* parent() { return &parent_; }
   TestView* child() { return child_; }
   TestBoundsAnimator* animator() { return &animator_; }
 
  private:
-  base::MessageLoopForUI message_loop_;
+  base::test::ScopedTaskEnvironment scoped_task_environment_;
   TestView parent_;
   TestView* child_;  // Owned by |parent_|.
   TestBoundsAnimator animator_;
 
   DISALLOW_COPY_AND_ASSIGN(BoundsAnimatorTest);
 };
 
 // Checks animate view to.
 TEST_F(BoundsAnimatorTest, AnimateViewTo) {
   gfx::Rect initial_bounds(0, 0, 10, 10);
@@ skipping 62 matching lines @@
 
   // Shouldn't be animating now.
   EXPECT_FALSE(animator()->IsAnimating());
 
   // Stopping should both cancel the delegate and delete it.
   EXPECT_TRUE(OwnedDelegate::GetAndClearDeleted());
   EXPECT_TRUE(OwnedDelegate::GetAndClearCanceled());
 }
 
 }  // namespace views