[ash-md] Fixed ShelfBackgroundAnimator to not snap target values when being preempted.

ash/common/shelf/shelf_background_animator_unittest.cc

 // Copyright 2016 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 "ash/common/shelf/shelf_background_animator.h"
 
 #include <memory>
 
 #include "ash/animation/animation_change_type.h"
 #include "ash/common/shelf/shelf_background_animator_observer.h"
@@ skipping 260 matching lines @@
 
   const gfx::SlideAnimation* animator = test_api_->animator();
   EXPECT_TRUE(animator);
 
   EXPECT_NE(SHELF_BACKGROUND_OVERLAP, test_api_->previous_background_type());
   PaintBackground(SHELF_BACKGROUND_OVERLAP, AnimationChangeType::ANIMATE);
 
   EXPECT_NE(animator, test_api_->animator());
 }
 
-TEST_F(ShelfBackgroundAnimatorTest,
-       AnimationProgressesToTargetWhenStoppingUnfinishedAnimator) {
-  PaintBackground(SHELF_BACKGROUND_OVERLAP, AnimationChangeType::ANIMATE);
-
-  EXPECT_NE(kShelfTranslucentAlpha, observer_.GetBackgroundAlpha());
-  EXPECT_NE(0, observer_.GetItemBackgroundAlpha());
-
-  test_api_->animator()->Stop();
-
-  EXPECT_EQ(kShelfTranslucentAlpha, observer_.GetBackgroundAlpha());
-  EXPECT_EQ(0, observer_.GetItemBackgroundAlpha());
-}
-
 // Verify observers are always notified, even when alpha values don't change.
 TEST_F(ShelfBackgroundAnimatorTest,
        ObserversAreNotifiedWhenSnappingToSameTargetBackground) {
   PaintBackground(SHELF_BACKGROUND_DEFAULT);
   SetColorValuesOnObserver(kDummyColor);
   PaintBackground(SHELF_BACKGROUND_DEFAULT);
 
   EXPECT_NE(observer_.background_color(), kDummyColor);
   EXPECT_NE(observer_.item_background_color(), kDummyColor);
 }
 
 }  // namespace ash