Bug 1689546 - Run overscroll-behavior.html with test.events.async.enabled=true. r=hiro

Depends on D177097

Differential Revision: https://phabricator.services.mozilla.com/D177098

testing/web-platform/meta/css/css-overscroll-behavior/overscroll-behavior.html.ini

@@ -1,3 +1,6 @@
 [overscroll-behavior.html]
   [overscroll-behavior prevents scroll-propagation in the area and direction as specified]
-    expected: FAIL
+    expected:
+      if os == "android": FAIL
+      PASS
+  prefs: [test.events.async.enabled:true]