flashlsFlowPlayer.swf : dispatch FINISH event in a different way
mimic the way it is dispatched in other StreamProvider. refer to https://github.com/flowplayer/flash/blob/1caea54d3e7fa66b6496d556998052507a6d05a4/plugins/rtmp/src/actionscript/org/flowplayer/rtmp/RTMPStreamProvider.as#L148 for example
related to https://github.com/mangui/flashls/issues/95