[ash-md] Remove non-md code from the Shelf background animations.

ash/common/shelf/shelf_background_animator.cc

Index: ash/common/shelf/shelf_background_animator.cc
diff --git a/ash/common/shelf/shelf_background_animator.cc b/ash/common/shelf/shelf_background_animator.cc
index ce9628f476f2125a5b53e54e370f1c105d34cc7c..2ebf9f012b950117412c3322505c5554cf26cebb 100644
--- a/ash/common/shelf/shelf_background_animator.cc
+++ b/ash/common/shelf/shelf_background_animator.cc
@@ -50,7 +50,6 @@ void ShelfBackgroundAnimator::RemoveObserver(
 void ShelfBackgroundAnimator::Initialize(
     ShelfBackgroundAnimatorObserver* observer) const {
   observer->UpdateShelfOpaqueBackground(opaque_background_animator_->alpha());
-  observer->UpdateShelfAssetBackground(asset_background_animator_->alpha());
   observer->UpdateShelfItemBackground(item_background_animator_->alpha());
 }
 
@@ -90,9 +89,6 @@ void ShelfBackgroundAnimator::OnAlphaChanged(BackgroundAnimator* animator,
   if (animator == opaque_background_animator_.get()) {
     for (auto& observer : observers_)
       observer.UpdateShelfOpaqueBackground(alpha);
-  } else if (animator == asset_background_animator_.get()) {
-    for (auto& observer : observers_)
-      observer.UpdateShelfAssetBackground(alpha);
   } else if (animator == item_background_animator_.get()) {
     for (auto& observer : observers_)
       observer.UpdateShelfItemBackground(alpha);
@@ -113,8 +109,6 @@ void ShelfBackgroundAnimator::AnimateBackground(
   bool show_background = true;
   if (can_reuse_animators_ && previous_background_type_ == background_type) {
     DCHECK_EQ(opaque_background_animator_->paints_background(),
-              asset_background_animator_->paints_background());
-    DCHECK_EQ(asset_background_animator_->paints_background(),
               item_background_animator_->paints_background());
 
     show_background = !opaque_background_animator_->paints_background();
@@ -132,7 +126,6 @@ void ShelfBackgroundAnimator::AnimateBackground(
 
   opaque_background_animator_->SetPaintsBackground(show_background,
                                                    change_type);
-  asset_background_animator_->SetPaintsBackground(show_background, change_type);
   item_background_animator_->SetPaintsBackground(show_background, change_type);
 
   if (target_background_type_ != background_type) {
@@ -146,8 +139,6 @@ void ShelfBackgroundAnimator::CreateAnimators(
     BackgroundAnimatorChangeType change_type) {
   const int opaque_background_alpha =
       opaque_background_animator_ ? opaque_background_animator_->alpha() : 0;
-  const int asset_background_alpha =
-      asset_background_animator_ ? asset_background_animator_->alpha() : 0;
   const int item_background_alpha =
       item_background_animator_ ? item_background_animator_->alpha() : 0;
 
@@ -159,8 +150,6 @@ void ShelfBackgroundAnimator::CreateAnimators(
       duration_ms = is_material ? 500 : 1000;
       opaque_background_animator_.reset(
           new BackgroundAnimator(this, opaque_background_alpha, 0));
-      asset_background_animator_.reset(
-          new BackgroundAnimator(this, asset_background_alpha, 0));
       item_background_animator_.reset(
           new BackgroundAnimator(this, item_background_alpha,
                                  GetShelfConstant(SHELF_BACKGROUND_ALPHA)));
@@ -170,9 +159,6 @@ void ShelfBackgroundAnimator::CreateAnimators(
       opaque_background_animator_.reset(new BackgroundAnimator(
           this, opaque_background_alpha,
           is_material ? GetShelfConstant(SHELF_BACKGROUND_ALPHA) : 0));
-      asset_background_animator_.reset(new BackgroundAnimator(
-          this, asset_background_alpha,
-          is_material ? 0 : GetShelfConstant(SHELF_BACKGROUND_ALPHA)));
       item_background_animator_.reset(new BackgroundAnimator(
           this, item_background_alpha,
           is_material ? 0 : GetShelfConstant(SHELF_BACKGROUND_ALPHA)));
@@ -181,24 +167,18 @@ void ShelfBackgroundAnimator::CreateAnimators(
       duration_ms = is_material ? 250 : 1000;
       opaque_background_animator_.reset(
           new BackgroundAnimator(this, opaque_background_alpha, kMaxAlpha));
-      asset_background_animator_.reset(new BackgroundAnimator(
-          this, asset_background_alpha,
-          is_material ? 0 : GetShelfConstant(SHELF_BACKGROUND_ALPHA)));
       item_background_animator_.reset(new BackgroundAnimator(
           this, item_background_alpha, is_material ? 0 : kMaxAlpha));
       break;
   }
 
   opaque_background_animator_->SetDuration(duration_ms);
-  asset_background_animator_->SetDuration(duration_ms);
   item_background_animator_->SetDuration(duration_ms);
 }
 
 void ShelfBackgroundAnimator::StopAnimators() {
   if (opaque_background_animator_)
     opaque_background_animator_->Stop();
-  if (asset_background_animator_)
-    asset_background_animator_->Stop();
   if (item_background_animator_)
     item_background_animator_->Stop();
 }