dispatchEvent should not trigger default actions
Note this tid-bit:
"The above doesn't happen for arbitrary synthetic events dispatched by author script. However, the click() method can be used to make it happen programmatically."
This came up in the context of https://bugs.webkit.org/show_bug.cgi?id=64580.
I suspect that we should fix https://bugs.webkit.org/show_bug.cgi?id=27880 along with this. It is important that people have a programmatic way to "click" on an element if synthetic "click" events are going to be neutered.