Revert "desks: Speculative fix for crash."

This reverts commit 536b412d.

Reason for revert: the test is failing on Linux Chromium OS ASan LSan Tests, crbug.com/1149939

Original change's description:
> desks: Speculative fix for crash.
>
> The previous attempt [1] added checks for whether the starting or ending
> screenshot was taken. In the case of the starting screenshot missing, it
> would signal the animation to remove some RootWindowDeskSwitchAnimators,
> leading to a vector out of bounds.
>
> [1] https://chromium-review.googlesource.com/c/chromium/src/+/2506356
>
> Bug: 1148607
> Test: added regression test
> Change-Id: I7f14df877cb93619a0ca8a85f5d0ad434dda3ad2
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2536934
> Commit-Queue: Sammie Quon <sammiequon@chromium.org>
> Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#828034}

TBR=afakhry@chromium.org,sammiequon@chromium.org

Change-Id: I27cc6811a5edd38a56eb82f20752638351e2b2df
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1148607
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2544443Reviewed-by: Ganggui Tang <gogerald@chromium.org>
Commit-Queue: Ganggui Tang <gogerald@chromium.org>
Cr-Commit-Position: refs/heads/master@{#828204}

ash/BUILD.gn

@@ -2256,7 +2256,6 @@ test("ash_unittests") {
     "wm/container_finder_unittest.cc",
     "wm/default_window_resizer_unittest.cc",
     "wm/desks/autotest_desks_api_unittests.cc",
-    "wm/desks/desk_animation_impl_unittest.cc",
     "wm/desks/desks_unittests.cc",
     "wm/desks/root_window_desk_switch_animator_unittest.cc",
     "wm/drag_window_resizer_unittest.cc",

ash/wm/desks/desk_animation_base.cc

@@ -128,9 +128,6 @@ void DeskAnimationBase::OnDeskSwitchAnimationFinished() {
   for (auto& observer : controller_->observers_)
     observer.OnDeskSwitchAnimationFinished();
 
-  if (skip_notify_controller_on_animation_finished_for_testing_)
-    return;
-
   controller_->OnAnimationFinished(this);
   // `this` is now deleted.
 }

ash/wm/desks/desk_animation_base.h

@@ -5,7 +5,6 @@
 #ifndef ASH_WM_DESKS_DESK_ANIMATION_BASE_H_
 #define ASH_WM_DESKS_DESK_ANIMATION_BASE_H_
 
-#include "ash/ash_export.h"
 #include "ash/public/cpp/metrics_util.h"
 #include "ash/wm/desks/desks_histogram_enums.h"
 #include "ash/wm/desks/root_window_desk_switch_animator.h"
@@ -20,8 +19,7 @@ class DesksController;
 // such as DeskActivationAnimation and DeskRemovalAnimation implement the
 // abstract interface of this class to handle the unique operations specific to
 // each animation type.
-class ASH_EXPORT DeskAnimationBase
-    : public RootWindowDeskSwitchAnimator::Delegate {
+class DeskAnimationBase : public RootWindowDeskSwitchAnimator::Delegate {
  public:
   DeskAnimationBase(DesksController* controller,
                     int ending_desk_index,
@@ -58,10 +56,6 @@ class ASH_EXPORT DeskAnimationBase
   void OnDeskSwitchAnimationFinished() override;
   void OnVisibleDeskChanged() override;
 
-  void set_skip_notify_controller_on_animation_finished_for_testing(bool val) {
-    skip_notify_controller_on_animation_finished_for_testing_ = val;
-  }
-
   RootWindowDeskSwitchAnimator* GetFirstDeskSwitchAnimatorForTesting() const;
 
  protected:
@@ -103,12 +97,6 @@ class ASH_EXPORT DeskAnimationBase
 
   // ThroughputTracker used for measuring this animation smoothness.
   ui::ThroughputTracker throughput_tracker_;
-
-  // If true, do not notify |controller_| when
-  // OnDeskSwitchAnimationFinished() is called. This class and
-  // DeskController are tied together in production code, but may not be in a
-  // test scenario.
-  bool skip_notify_controller_on_animation_finished_for_testing_ = false;
 };
 
 }  // namespace ash

ash/wm/desks/desk_animation_impl.cc

@@ -182,8 +182,9 @@ bool DeskActivationAnimation::EndSwipeAnimation() {
   // and update their ending desk index. When the animation is finished we will
   // activate that desk.
   for (const auto& animator : desk_switch_animators_)
-    ending_desk_index_ = animator->EndSwipeAnimation();
+    animator->EndSwipeAnimation();
 
+  ending_desk_index_ = desk_switch_animators_[0]->ending_desk_index();
   return true;
 }
 

ash/wm/desks/desk_animation_impl.h

@@ -5,7 +5,6 @@
 #ifndef ASH_WM_DESKS_DESK_ANIMATION_IMPL_H_
 #define ASH_WM_DESKS_DESK_ANIMATION_IMPL_H_
 
-#include "ash/ash_export.h"
 #include "ash/public/cpp/metrics_util.h"
 #include "ash/wm/desks/desk_animation_base.h"
 #include "ash/wm/desks/desks_histogram_enums.h"
@@ -15,7 +14,7 @@ namespace ash {
 class DesksController;
 class PresentationTimeRecorder;
 
-class ASH_EXPORT DeskActivationAnimation : public DeskAnimationBase {
+class DeskActivationAnimation : public DeskAnimationBase {
  public:
   DeskActivationAnimation(DesksController* controller,
                           int starting_desk_index,

ash/wm/desks/desk_animation_impl_unittest.cc

-// Copyright 2020 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/desks/desk_animation_impl.h"
-
-#include "ash/public/cpp/ash_features.h"
-#include "ash/test/ash_test_base.h"
-#include "ash/wm/desks/desks_controller.h"
-#include "ash/wm/desks/desks_histogram_enums.h"
-#include "base/test/scoped_feature_list.h"
-
-namespace ash {
-
-using DeskActivationAnimationTest = AshTestBase;
-
-// Tests that there is no crash when ending a swipe animation before the
-// starting screenshot has been taken. Regression test for
-// https://crbug.com/1148607.
-TEST_F(DeskActivationAnimationTest, EndSwipeBeforeStartingScreenshot) {
-  base::test::ScopedFeatureList feature_list;
-  feature_list.InitAndEnableFeature(features::kEnhancedDeskAnimations);
-
-  auto* desks_controller = DesksController::Get();
-  desks_controller->NewDesk(DesksCreationRemovalSource::kButton);
-
-  DeskActivationAnimation animation(desks_controller, 0, 1,
-                                    DesksSwitchSource::kDeskSwitchTouchpad,
-                                    /*update_window_activation=*/false);
-  animation.set_skip_notify_controller_on_animation_finished_for_testing(true);
-  animation.Launch();
-  animation.UpdateSwipeAnimation(10);
-  animation.EndSwipeAnimation();
-}
-
-}  // namespace ash

ash/wm/desks/root_window_desk_switch_animator.cc

@@ -75,8 +75,6 @@ void TakeScreenshot(
       viz::CopyOutputRequest::ResultFormat::RGBA_TEXTURE,
       std::move(on_screenshot_taken));
   screenshot_request->set_area(request_bounds);
-  screenshot_request->set_result_task_runner(
-      base::SequencedTaskRunnerHandle::Get());
   screenshot_layer->RequestCopyOfOutput(std::move(screenshot_request));
 }
 
@@ -327,7 +325,7 @@ bool RootWindowDeskSwitchAnimator::UpdateSwipeAnimation(float scroll_delta_x) {
   return true;
 }
 
-int RootWindowDeskSwitchAnimator::EndSwipeAnimation() {
+void RootWindowDeskSwitchAnimator::EndSwipeAnimation() {
   // If the starting screenshot has not finished, just let our delegate know
   // that the desk animation is finished (and |this| will soon be deleted), and
   // go back to the starting desk.
@@ -335,7 +333,7 @@ int RootWindowDeskSwitchAnimator::EndSwipeAnimation() {
     animation_finished_ = true;
     ending_desk_index_ = starting_desk_index_;
     delegate_->OnDeskSwitchAnimationFinished();
-    return ending_desk_index_;
+    return;
   }
 
   // If the ending desk screenshot has not finished, |visible_desk_index_| will
@@ -346,7 +344,6 @@ int RootWindowDeskSwitchAnimator::EndSwipeAnimation() {
 
   ending_desk_index_ = visible_desk_index_;
   StartAnimation();
-  return ending_desk_index_;
 }
 
 void RootWindowDeskSwitchAnimator::OnImplicitAnimationsCompleted() {

ash/wm/desks/root_window_desk_switch_animator.h

@@ -266,8 +266,8 @@ class ASH_EXPORT RootWindowDeskSwitchAnimator
   bool UpdateSwipeAnimation(float scroll_delta_x);
 
   // Called when a user ends a touchpad swipe. This will animate to the most
-  // visible desk, whose index is also returned.
-  int EndSwipeAnimation();
+  // visible desk.
+  void EndSwipeAnimation();
 
   // ui::ImplicitAnimationObserver:
   void OnImplicitAnimationsCompleted() override;