Revert of Replaced BackgroundAnimator with ShelfBackgroundAnimator.

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
deleted file mode 100644
index 072f59ea21d1bb6a5bf11a8fa7a419bd3d25cc09..0000000000000000000000000000000000000000
--- a/ash/common/shelf/shelf_background_animator.cc
+++ /dev/null
@@ -1,202 +0,0 @@
-// 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 <algorithm>
-
-#include "ash/common/material_design/material_design_controller.h"
-#include "ash/common/shelf/shelf_background_animator_observer.h"
-#include "ash/common/shelf/shelf_constants.h"
-#include "ash/common/shelf/wm_shelf.h"
-
-namespace ash {
-
-namespace {
-// The total number of animators that will call BackgroundAnimationEnded().
-const int kNumAnimators = 3;
-
-const int kMaxAlpha = 255;
-}  // namespace
-
-ShelfBackgroundAnimator::ShelfBackgroundAnimator(
-    ShelfBackgroundType background_type,
-    WmShelf* wm_shelf)
-    : wm_shelf_(wm_shelf) {
-  if (wm_shelf_)
-    wm_shelf_->AddObserver(this);
-  // Initialize animators so that adding observers get notified with consistent
-  // values.
-  AnimateBackground(background_type, BACKGROUND_CHANGE_IMMEDIATE);
-}
-
-ShelfBackgroundAnimator::~ShelfBackgroundAnimator() {
-  if (wm_shelf_)
-    wm_shelf_->RemoveObserver(this);
-}
-
-void ShelfBackgroundAnimator::AddObserver(
-    ShelfBackgroundAnimatorObserver* observer) {
-  observers_.AddObserver(observer);
-
-  observer->UpdateShelfOpaqueBackground(opaque_background_animator_->alpha());
-  observer->UpdateShelfAssetBackground(asset_background_animator_->alpha());
-  observer->UpdateShelfItemBackground(item_background_animator_->alpha());
-}
-
-void ShelfBackgroundAnimator::RemoveObserver(
-    ShelfBackgroundAnimatorObserver* observer) {
-  observers_.RemoveObserver(observer);
-}
-
-void ShelfBackgroundAnimator::PaintBackground(
-    ShelfBackgroundType background_type,
-    BackgroundAnimatorChangeType change_type) {
-  if (target_background_type_ == background_type &&
-      change_type == BACKGROUND_CHANGE_ANIMATE) {
-    return;
-  }
-
-  AnimateBackground(background_type, change_type);
-}
-
-void ShelfBackgroundAnimator::OnBackgroundTypeChanged(
-    ShelfBackgroundType background_type,
-    BackgroundAnimatorChangeType change_type) {
-  PaintBackground(background_type, change_type);
-}
-
-void ShelfBackgroundAnimator::UpdateBackground(BackgroundAnimator* animator,
-                                               int alpha) {
-  OnAlphaChanged(animator, alpha);
-}
-
-void ShelfBackgroundAnimator::BackgroundAnimationEnded(
-    BackgroundAnimator* animator) {
-  ++successful_animator_count_;
-  DCHECK_LE(successful_animator_count_, kNumAnimators);
-  // UpdateBackground() is only called when alpha values change, this ensures
-  // observers are always notified for every background change.
-  OnAlphaChanged(animator, animator->alpha());
-}
-
-void ShelfBackgroundAnimator::OnAlphaChanged(BackgroundAnimator* animator,
-                                             int alpha) {
-  if (animator == opaque_background_animator_.get()) {
-    FOR_EACH_OBSERVER(ShelfBackgroundAnimatorObserver, observers_,
-                      UpdateShelfOpaqueBackground(alpha));
-  } else if (animator == asset_background_animator_.get()) {
-    FOR_EACH_OBSERVER(ShelfBackgroundAnimatorObserver, observers_,
-                      UpdateShelfAssetBackground(alpha));
-  } else if (animator == item_background_animator_.get()) {
-    FOR_EACH_OBSERVER(ShelfBackgroundAnimatorObserver, observers_,
-                      UpdateShelfItemBackground(alpha));
-  } else {
-    NOTREACHED();
-  }
-}
-
-void ShelfBackgroundAnimator::AnimateBackground(
-    ShelfBackgroundType background_type,
-    BackgroundAnimatorChangeType change_type) {
-  // Ensure BackgroundAnimationEnded() has been called for all the
-  // BackgroundAnimators owned by this so that |successful_animator_count_|
-  // is stable and doesn't get updated as a side effect of destroying/animating
-  // the animators.
-  StopAnimators();
-
-  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();
-  } else {
-    CreateAnimators(background_type, change_type);
-
-    // If all the previous animators completed successfully and the animation
-    // was between 2 distinct states, then the last alpha values are valid
-    // end state values.
-    can_reuse_animators_ = target_background_type_ != background_type &&
-                           successful_animator_count_ == kNumAnimators;
-  }
-
-  successful_animator_count_ = 0;
-
-  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) {
-    previous_background_type_ = target_background_type_;
-    target_background_type_ = background_type;
-  }
-}
-
-void ShelfBackgroundAnimator::CreateAnimators(
-    ShelfBackgroundType background_type,
-    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;
-
-  const bool is_material = MaterialDesignController::IsShelfMaterial();
-  int duration_ms = 0;
-
-  switch (background_type) {
-    case SHELF_BACKGROUND_DEFAULT:
-      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)));
-      break;
-    case SHELF_BACKGROUND_OVERLAP:
-      duration_ms = is_material ? 500 : 1000;
-      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)));
-      break;
-    case SHELF_BACKGROUND_MAXIMIZED:
-      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();
-}
-
-}  // namespace ash