According to the UI Events specification un-trusted events (i.e. those created by JavaScript) should not invoke the default action. 'click' is the only event that is a legacy permitted case. The isTrusted support was added in https://www.chromestatus.com/features/6461137440735232 which identifies trusted events from un-trusted events. We wish to prevent synthetic events from executing the default action, aligning with Firefox and IE.