Bug 1761042 [wpt PR 33328] - Remove redundant tests for scrollend / o…

…verscroll events fired to document., a=testonly

Automatic update from web-platform-tests
Remove redundant tests for scrollend / overscroll events fired to document.

The WPT version of the scrollend test could erroneously pass even if the
second scroll in the test did not fire a scrollend event. Fixed by
ensuring that the scrollend listeners for the directional scrolls are
not both armed at the same time.

Bug: 1309479
Change-Id: I1a4c929cbb39d1173269575a2be289a090d1394b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3546082
Reviewed-by: Steve Kobes <skobes@chromium.org>
Commit-Queue: Kevin Ellis <kevers@chromium.org>
Cr-Commit-Position: refs/heads/main@{#986672}

--

wpt-commits: d5d1e2cd0ff9f729f1ac31bc3f1695bf6fa98c1b
wpt-pr: 33328

testing/web-platform/tests/dom/events/scrolling/scrollend-event-fired-to-document.html

@@ -41,22 +41,24 @@
   assert_true(event.bubbles);
   vertical_scrollend_arrived = true;
 }
-document.addEventListener("scrollend", onHorizontalScrollEnd);
-document.addEventListener("scrollend", onVerticalScrollEnd);
 
 function runTest() {
   promise_test (async (t) => {
     // Make sure that no scrollend event is sent to target_div.
     target_div.addEventListener("scrollend",
         t.unreached_func("target_div got unexpected scrollend event."));
     await waitForCompositorCommit();
+
     // Scroll left on target div and wait for the doc to get scrollend event.
+    document.addEventListener("scrollend", onHorizontalScrollEnd);
     await touchScrollInTarget(300, target_div, 'left');
     await waitFor(() => { return horizontal_scrollend_arrived; },
         'Document did not receive scrollend event after scroll left on target.');
     assert_equals(target_div.scrollLeft, 0);
+    document.removeEventListener("scrollend", onHorizontalScrollEnd);
 
     // Scroll up on target div and wait for the doc to get scrollend event.
+    document.addEventListener("scrollend", onVerticalScrollEnd);
     await touchScrollInTarget(300, target_div, 'up');
     await waitFor(() => { return vertical_scrollend_arrived; },
         'Document did not receive scrollend event after scroll up on target.');