Count stageclick events from the SWF as user activity

[dmlap]

IE11 on Win8.1 RT does not report click events on the SWF object. The SWF already triggers stageclick events whenever a click/touch is detected however, so we can use those to keep the control bar from hiding forever.

[heff]

Pulling this in. If we wanted to actually trigger a click with this as well, so toggling the video playback still worked, how complicated does it get?

[dmlap]

@heff: we could get close with player.on('stageclick', function() { player.trigger('click'); }). We'd want to test it out pretty thoroughly beforehand to make sure it didn't break any assumptions we're making elsewhere, however. It wouldn't be a native click event and we might see inconsistent behavior as a result. A more targeted approach might be to toggle the playback state in the stageclick handler directly.