Revert "ambient: Show lockscreen contents on detecting user interaction."

This reverts commit 660c9cef.

Reason for revert: AmbientContainerViewTest.MouseClickClosesWidgetAndStopsTimer failing deterministically on several linux-chromeos bots. Please see https://crbug.com/1068745 for more information.

Original change's description:
> ambient: Show lockscreen contents on detecting user interaction.
> 
> In ambient mode, when user interacting with the background image by
> mouse or gesture, lock screen contents (login pod and media control
> view) need be shown on top for users to either do re-authentication,
> or media control.
> 
> This CL implements a prototype of this view transaction by:
> 1. Show the lock screen contents, and
> 2. Fade-out the current shown image.
> 
> Bug: b/149246238
> Test: manually.
> Change-Id: Ie31c666cdfaddefc863ff8173dc185d73ef19178
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2110689
> Commit-Queue: Meilin Wang <meilinw@chromium.org>
> Reviewed-by: Xiaohui Chen <xiaohuic@chromium.org>
> Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#757120}

TBR=xiyuan@chromium.org,xiaohuic@chromium.org,wutao@chromium.org,meilinw@chromium.org

Change-Id: I395a7c02c6aa292f66ca5d9b4aefa9156e057773
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: b/149246238, 1068745
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2139369Reviewed-by: Darwin Huang <huangdarwin@chromium.org>
Commit-Queue: Darwin Huang <huangdarwin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#757223}

ash/ambient/ambient_controller.cc

@@ -11,7 +11,6 @@
 #include "ash/ambient/ui/ambient_container_view.h"
 #include "ash/ambient/util/ambient_util.h"
 #include "ash/assistant/assistant_controller.h"
-#include "ash/assistant/util/animation_util.h"
 #include "ash/login/ui/lock_screen.h"
 #include "ash/public/cpp/ambient/ambient_mode_state.h"
 #include "ash/public/cpp/ambient/ambient_prefs.h"
@@ -94,17 +93,20 @@ void AmbientController::OnAmbientModeEnabled(bool enabled) {
 }
 
 void AmbientController::OnLockStateChanged(bool locked) {
-  if (locked) {
-    // Show ambient mode when entering lock screen.
+  if (!locked) {
+    // We should already exit ambient mode at this time, as the ambient
+    // container needs to be closed to uncover the login port for
+    // re-authentication.
     DCHECK(!container_view_);
-    Show();
-  } else {
-    // Destroy ambient mode after user re-login.
-    Destroy();
+    return;
   }
+
+  // Show the ambient container on top of the lock screen.
+  DCHECK(!container_view_);
+  Start();
 }
 
-void AmbientController::Show() {
+void AmbientController::Start() {
   if (!CanStartAmbientMode()) {
     // TODO(wutao): Show a toast to indicate that Ambient mode is not ready.
     return;
@@ -119,34 +121,14 @@ void AmbientController::Show() {
   ambient_state_.SetAmbientModeEnabled(true);
 }
 
-void AmbientController::Destroy() {
+void AmbientController::Stop() {
   ambient_state_.SetAmbientModeEnabled(false);
 }
-
 void AmbientController::Toggle() {
   if (container_view_)
-    Destroy();
+    Stop();
   else
-    Show();
-}
-
-void AmbientController::OnBackgroundPhotoEvents() {
-  refresh_timer_.Stop();
-
-  // Move the |AmbientModeContainer| beneath the |LockScreenWidget| to show the
-  // lock screen contents on top before the fade-out animation.
-  auto* ambient_window = container_view_->GetWidget()->GetNativeWindow();
-  ambient_window->parent()->StackChildAtBottom(ambient_window);
-
-  // Start fading out the current background photo.
-  StartFadeOutAnimation();
-}
-
-void AmbientController::StartFadeOutAnimation() {
-  // We fade out the |PhotoView| on its own layer instead of using the general
-  // layer of the widget, otherwise it will reveal the color of the lockscreen
-  // wallpaper beneath.
-  container_view_->FadeOutPhotoView();
+    Start();
 }
 
 void AmbientController::CreateContainerView() {
@@ -164,6 +146,9 @@ void AmbientController::DestroyContainerView() {
 }
 
 void AmbientController::RefreshImage() {
+  if (!PhotoController::Get())
+    return;
+
   if (photo_model_.ShouldFetchImmediately()) {
     // TODO(b/140032139): Defer downloading image if it is animating.
     base::SequencedTaskRunnerHandle::Get()->PostDelayedTask(

ash/ambient/ambient_controller.h

@@ -45,21 +45,12 @@ class ASH_EXPORT AmbientController : public views::WidgetObserver,
   // SessionObserver:
   void OnLockStateChanged(bool locked) override;
 
-  // Creates and displays the ambient mode screen on top of the lock screen.
-  void Show();
-  // Destroys the ambient mode screen widget.
-  void Destroy();
-  // Toggle between show and destroy the ambient mode screen.
-  // Should be removed once we delete the shortcut entry point.
+  void Start();
+  void Stop();
   void Toggle();
 
   PhotoModel* photo_model() { return &photo_model_; }
 
-  // Handles user interactions on the background photo. For now the behavior
-  // is showing lock screen contents (login pod and media control view) on top
-  // while fading-out the current shown image.
-  void OnBackgroundPhotoEvents();
-
   AmbientContainerView* get_container_view_for_testing() {
     return container_view_;
   }
@@ -78,8 +69,6 @@ class ASH_EXPORT AmbientController : public views::WidgetObserver,
   void GetNextImage();
   void OnPhotoDownloaded(bool success, const gfx::ImageSkia& image);
 
-  void StartFadeOutAnimation();
-
   AmbientViewDelegateImpl delegate_{this};
   AmbientContainerView* container_view_ = nullptr;   // Owned by view hierarchy.
   PhotoModel photo_model_;

ash/ambient/ambient_view_delegate_impl.cc

@@ -21,7 +21,18 @@ PhotoModel* AmbientViewDelegateImpl::GetPhotoModel() {
 }
 
 void AmbientViewDelegateImpl::OnBackgroundPhotoEvents() {
-  ambient_controller_->OnBackgroundPhotoEvents();
+  // Exit ambient mode by closing the widget when user interacts with the
+  // background photo using mouse or gestures. We do this asynchronously to
+  // ensure that for a mouse moved event, the widget will be destroyed *after*
+  // its cursor has been updated in |RootView::OnMouseMoved|.
+  base::SequencedTaskRunnerHandle::Get()->PostTask(
+      FROM_HERE,
+      base::BindOnce(
+          [](const base::WeakPtr<AmbientViewDelegateImpl>& weak_ptr) {
+            if (weak_ptr)
+              weak_ptr->ambient_controller_->Stop();
+          },
+          weak_factory_.GetWeakPtr()));
 }
 
 }  // namespace ash

ash/ambient/ui/ambient_container_view.cc

@@ -12,7 +12,6 @@
 #include "ash/ambient/ui/photo_view.h"
 #include "ash/ambient/util/ambient_util.h"
 #include "ash/assistant/assistant_controller.h"
-#include "ash/assistant/util/animation_util.h"
 #include "ash/login/ui/lock_screen.h"
 #include "ash/public/cpp/shell_window_ids.h"
 #include "ash/shell.h"
@@ -28,12 +27,6 @@ namespace {
 // Ambient Assistant container view appearance.
 constexpr int kAmbientAssistantContainerViewPreferredHeightDip = 128;
 
-// TODO(meilinw): temporary values for dev purpose, need to be updated with the
-// final spec.
-constexpr float kBackgroundPhotoOpacity = 0.5f;
-constexpr base::TimeDelta kBackgroundPhotoFadeOutAnimationDuration =
-    base::TimeDelta::FromMilliseconds(500);
-
 aura::Window* GetContainer() {
   aura::Window* container = nullptr;
   if (ambient::util::IsShowing(LockScreen::ScreenType::kLock))
@@ -48,7 +41,7 @@ void CreateWidget(AmbientContainerView* view) {
   params.parent = GetContainer();
   params.type = views::Widget::InitParams::TYPE_WINDOW_FRAMELESS;
   params.delegate = view;
-  params.name = "AmbientModeContainer";
+  params.name = view->GetClassName();
 
   views::Widget* widget = new views::Widget;
   widget->Init(std::move(params));
@@ -83,16 +76,6 @@ void AmbientContainerView::Layout() {
                 kAmbientAssistantContainerViewPreferredHeightDip));
 }
 
-void AmbientContainerView::FadeOutPhotoView() {
-  DCHECK(photo_view_);
-
-  photo_view_->layer()->GetAnimator()->StartAnimation(
-      assistant::util::CreateLayerAnimationSequence(
-          assistant::util::CreateOpacityElement(
-              kBackgroundPhotoOpacity,
-              kBackgroundPhotoFadeOutAnimationDuration)));
-}
-
 void AmbientContainerView::Init() {
   CreateWidget(this);
   // TODO(b/139954108): Choose a better dark mode theme color.

ash/ambient/ui/ambient_container_view.h

@@ -26,9 +26,6 @@ class ASH_EXPORT AmbientContainerView : public views::WidgetDelegateView {
   gfx::Size CalculatePreferredSize() const override;
   void Layout() override;
 
-  // Fade out the background photo.
-  void FadeOutPhotoView();
-
  private:
   void Init();
 

ash/ambient/ui/ambient_view_delegate.h

@@ -17,7 +17,7 @@ class ASH_EXPORT AmbientViewDelegate {
 
   virtual PhotoModel* GetPhotoModel() = 0;
 
-  // Invoked when user interacting with the background photo using mouse,
+  // Invoked when user interacts with the background photo using mouse,
   // touchpad, or touchscreen.
   virtual void OnBackgroundPhotoEvents() = 0;
 };