In https://github.com/w3c/web-platform-tests/pull/6897 a test_driver.click() mechanism was added to web-platform-tests. When this is imported, we need to implement the glue in Blink and make sure that uievents/order-of-events/mouse-events/click-cancel.html passes.
Comment 1 by foolip@chromium.org
, Nov 3 2017