Make flaky snap fling test fail quickly
The flaky test in the linked bug appears to be timing out while waiting
for a scrollend event. This patch modifies the test to listen for
pointer events which signal whether or not a scroll is
happening and allows us to fail/bail early instead of wait for a
timeout.
Bug: 380534434
Change-Id: I2d203cc44b93e8c4c83f9644748916c1d65acbf7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6049312
Reviewed-by: Kevin Ellis kevers@chromium.org
Commit-Queue: David Awogbemila awogbemila@chromium.org
Cr-Commit-Position: refs/heads/main@{#1388805}