Regression (r268615) : [ macOS ] webanimations/relative-ordering-of-t…

…ranslate-and-rotate-properties-accelerated.html is a flaky image failure

https://bugs.webkit.org/show_bug.cgi?id=230863
<rdar://83593809>

Patch by Antoine Quint <graouts@apple.com> on 2022-06-13
Reviewed by Dean Jackson.

Use the tried and true technique of waiting for animations to be ready and three animation frames
to ensure all accelerated animations have been committed.

* LayoutTests/platform/mac-wk1/TestExpectations:
* LayoutTests/webanimations/resources/wait-until-animations-are-committed.js:

Canonical link: https://commits.webkit.org/251499@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@295494 268f45cc-cd09-0410-ab3c-d52691b4dbfc

LayoutTests/platform/mac-wk1/TestExpectations

@@ -1477,8 +1477,6 @@ webkit.org/b/223944 [ BigSur Debug ] imported/w3c/web-platform-tests/xhr/event-u
 # rdar://80342885 ([ Monterey wk1 arm64 ] webanimations/accelerated-transition-by-removing-property.html is a flaky image only failure)
 [ Monterey arm64 ] webanimations/accelerated-transition-by-removing-property.html [ Pass ImageOnlyFailure ]
 
-webkit.org/b/230863 webanimations/relative-ordering-of-translate-and-rotate-properties-accelerated.html [ Pass ImageOnlyFailure ]
-
 webkit.org/b/223816 [ arm64 ] platform/mac/fast/objc/webScriptObject-hasWebScriptKey.html [ Failure ]
 
 # rdar://80346975

LayoutTests/webanimations/resources/wait-until-animations-are-committed.js

@@ -1,15 +1,12 @@
 
 (async () => {
-    if (!window.testRunner)
-        return;
-
-    testRunner.waitUntilDone();
-
-    const script = document.createElement("script");
-    script.src = "../resources/ui-helper.js";
-    script.addEventListener("load", async event => {
-        await UIHelper.ensureStablePresentationUpdate();
-        testRunner.notifyDone();
-    });
-    document.body.appendChild(script);
+    window.testRunner?.waitUntilDone();
+
+    await Promise.all(document.getAnimations().map(animation => animation.ready));
+
+    await new Promise(requestAnimationFrame);
+    await new Promise(requestAnimationFrame);
+    await new Promise(requestAnimationFrame);
+
+    window.testRunner?.notifyDone();
 })();