[ScrollTimeline] Unconditionally detach compositor timeline during Do…

…cument::Shutdown()

Previously during the shutdown process the compositor timeline may not
be detached if it still has animation attached to it. Rather, it should
be detached unconditionally.

This patch moves the condition check to the call sites to make sure that
the timeline cannot be detached if it still has animation attached.

Bug: None
Change-Id: I0e9b02493ffab9521211a0723557dafa19917f00
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2167517
Reviewed-by: David Bokan <bokan@chromium.org>
Reviewed-by: Majid Valipour <majidvp@chromium.org>
Commit-Queue: Yi Gu <yigu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#763463}

third_party/blink/renderer/core/animation/animation.cc

@@ -2011,8 +2011,10 @@ void Animation::DetachCompositorTimeline() {
 
   compositor_timeline->AnimationDestroyed(*this);
 
-  if (compositor_timeline->GetAnimationTimeline()->IsScrollTimeline())
+  if (compositor_timeline->GetAnimationTimeline()->IsScrollTimeline() &&
+      !compositor_timeline->GetAnimationTimeline()->HasAnimation()) {
     document_->DetachCompositorTimeline(compositor_timeline);
+  }
 }
 
 void Animation::UpdateCompositorScrollTimeline() {

third_party/blink/renderer/core/dom/document.cc

@@ -2975,12 +2975,8 @@ void Document::DetachCompositorTimeline(
       !GetSettings()->GetAcceleratedCompositingEnabled())
     return;
 
-  // This requires detaching all animations from timeline first before detaching
-  // timeline.
-  if (timeline->GetAnimationTimeline()->IsScrollTimeline() &&
-      timeline->GetAnimationTimeline()->HasAnimation())
-    return;
-
+  // During Document::Shutdown() the timeline needs to be unconditionally
+  // detached.
   GetPage()->GetChromeClient().DetachCompositorAnimationTimeline(timeline,
                                                                  GetFrame());
 }

third_party/blink/renderer/modules/animationworklet/worklet_animation.cc

@@ -691,7 +691,8 @@ void WorkletAnimation::DestroyCompositorAnimation() {
 
   if (compositor_animation_) {
     if (compositor_timeline &&
-        compositor_timeline->GetAnimationTimeline()->IsScrollTimeline()) {
+        compositor_timeline->GetAnimationTimeline()->IsScrollTimeline() &&
+        !compositor_timeline->GetAnimationTimeline()->HasAnimation()) {
       document_->DetachCompositorTimeline(compositor_timeline);
     }