Fix flash source chooser

The radio buttons were not showing up in the flash player because the source-chooser was trying to find the video sources through media.children. However, for the flash player, media.children is undefined. Instead if we use the player's node, we can get to the source nodes. 

Additionally, the flash VideoElement code was not triggering a "canplay" event that the source-chooser plugin uses to determine when to play the newly loaded media. We trigger both the "loadeddata" and the "CANPLAY" events after connecting to the stream since at that point, the video will be playable. 

This PR's first commit also gets most of the tests passing.

Apologies for the diff of the VideoElement.as file, but it was a big pain not to change whitespace.