Reland of [ash-md] Fades overview header in and out

ash/wm/overview/scoped_overview_animation_settings_aura.cc

 // Copyright 2014 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/wm/overview/scoped_overview_animation_settings_aura.h"
 
 #include "ash/common/material_design/material_design_controller.h"
 #include "base/time/time.h"
 #include "ui/aura/window.h"
 #include "ui/compositor/layer.h"
+#include "ui/compositor/layer_animation_observer.h"
+#include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/gfx/animation/tween.h"
 
 namespace ash {
 
 namespace {
 
 // The time duration for transformation animations.
-const int kTransitionMilliseconds = 200;
+const int kTransitionMilliseconds = 300;
 
 // The time duration for fading out when closing an item. Only used with
 // Material Design.
 const int kCloseFadeOutMillisecondsMd = 50;
 
 // The time duration for scaling down when an item is closed. Only used with
 // Material Design.
 const int kCloseScaleMillisecondsMd = 100;
 
 // The time duration for widgets to fade in.
-const int kFadeInMilliseconds = 80;
+const int kFadeInMilliseconds = 60;
+
+// The time duration for widgets to fade out.
+const int kFadeOutDelayMilliseconds = kTransitionMilliseconds * 1 / 5;
+const int kFadeOutMilliseconds = kTransitionMilliseconds * 3 / 5;
 
 base::TimeDelta GetAnimationDuration(OverviewAnimationType animation_type) {
+  const bool material = ash::MaterialDesignController::IsOverviewMaterial();
   switch (animation_type) {
     case OVERVIEW_ANIMATION_NONE:
       return base::TimeDelta();
     case OVERVIEW_ANIMATION_ENTER_OVERVIEW_MODE_FADE_IN:
-      return base::TimeDelta::FromMilliseconds(kFadeInMilliseconds);
+      return base::TimeDelta::FromMilliseconds(
+          material ? kFadeInMilliseconds : kTransitionMilliseconds);
+    case OVERVIEW_ANIMATION_EXIT_OVERVIEW_MODE_FADE_OUT:
+      return base::TimeDelta::FromMilliseconds(kFadeOutMilliseconds);
     case OVERVIEW_ANIMATION_LAY_OUT_SELECTOR_ITEMS:
     case OVERVIEW_ANIMATION_RESTORE_WINDOW:
-    case OVERVIEW_ANIMATION_HIDE_WINDOW:
       return base::TimeDelta::FromMilliseconds(kTransitionMilliseconds);
     case OVERVIEW_ANIMATION_CLOSING_SELECTOR_ITEM:
       return base::TimeDelta::FromMilliseconds(kCloseScaleMillisecondsMd);
     case OVERVIEW_ANIMATION_CLOSE_SELECTOR_ITEM:
       return base::TimeDelta::FromMilliseconds(kCloseFadeOutMillisecondsMd);
   }
   NOTREACHED();
   return base::TimeDelta();
 }
 
 }  // namespace
 
 ScopedOverviewAnimationSettingsAura::ScopedOverviewAnimationSettingsAura(
     OverviewAnimationType animation_type,
     aura::Window* window)
-    : animation_settings_(window->layer()->GetAnimator()) {
+    : animation_settings_(new ui::ScopedLayerAnimationSettings(
+          window->layer()->GetAnimator())) {
+  const bool material = ash::MaterialDesignController::IsOverviewMaterial();
   switch (animation_type) {
     case OVERVIEW_ANIMATION_NONE:
-      animation_settings_.SetPreemptionStrategy(
+      animation_settings_->SetPreemptionStrategy(
           ui::LayerAnimator::REPLACE_QUEUED_ANIMATIONS);
       break;
     case OVERVIEW_ANIMATION_ENTER_OVERVIEW_MODE_FADE_IN:
+      if (material) {
+        animation_settings_->SetTweenType(gfx::Tween::EASE_IN);
+      } else {
+        window->layer()->GetAnimator()->SchedulePauseForProperties(
+            GetAnimationDuration(OverviewAnimationType::
+                                     OVERVIEW_ANIMATION_LAY_OUT_SELECTOR_ITEMS),
+            ui::LayerAnimationElement::OPACITY);
+      }
+      animation_settings_->SetPreemptionStrategy(
+          ui::LayerAnimator::REPLACE_QUEUED_ANIMATIONS);
+      break;
+    case OVERVIEW_ANIMATION_EXIT_OVERVIEW_MODE_FADE_OUT:
       window->layer()->GetAnimator()->SchedulePauseForProperties(
-          GetAnimationDuration(
-              OverviewAnimationType::OVERVIEW_ANIMATION_LAY_OUT_SELECTOR_ITEMS),
+          base::TimeDelta::FromMilliseconds(kFadeOutDelayMilliseconds),
           ui::LayerAnimationElement::OPACITY);
-      animation_settings_.SetPreemptionStrategy(
+      animation_settings_->SetTweenType(gfx::Tween::EASE_OUT);
+      animation_settings_->SetPreemptionStrategy(
           ui::LayerAnimator::REPLACE_QUEUED_ANIMATIONS);
       break;
     case OVERVIEW_ANIMATION_LAY_OUT_SELECTOR_ITEMS:
     case OVERVIEW_ANIMATION_RESTORE_WINDOW:
-      animation_settings_.SetPreemptionStrategy(
+      animation_settings_->SetPreemptionStrategy(
           ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
-      animation_settings_.SetTweenType(
-          ash::MaterialDesignController::IsOverviewMaterial()
-              ? gfx::Tween::EASE_IN_2
-              : gfx::Tween::FAST_OUT_SLOW_IN);
+      animation_settings_->SetTweenType(
+          material ? gfx::Tween::EASE_OUT : gfx::Tween::FAST_OUT_SLOW_IN);
       break;
     case OVERVIEW_ANIMATION_CLOSING_SELECTOR_ITEM:
     case OVERVIEW_ANIMATION_CLOSE_SELECTOR_ITEM:
-      animation_settings_.SetPreemptionStrategy(
+      animation_settings_->SetPreemptionStrategy(
           ui::LayerAnimator::ENQUEUE_NEW_ANIMATION);
-      animation_settings_.SetTweenType(gfx::Tween::EASE_OUT);
-      break;
-    case OVERVIEW_ANIMATION_HIDE_WINDOW:
-      animation_settings_.SetPreemptionStrategy(
-          ui::LayerAnimator::IMMEDIATELY_ANIMATE_TO_NEW_TARGET);
+      animation_settings_->SetTweenType(gfx::Tween::EASE_OUT);
       break;
   }
-  animation_settings_.SetTransitionDuration(
+  animation_settings_->SetTransitionDuration(
       GetAnimationDuration(animation_type));
 }
 
 ScopedOverviewAnimationSettingsAura::~ScopedOverviewAnimationSettingsAura() {}
 
+void ScopedOverviewAnimationSettingsAura::AddObserver(
+    ui::ImplicitAnimationObserver* observer) {
+  animation_settings_->AddObserver(observer);
+}
+
 }  // namespace ash