Trying to fix a player size issue on iPad.

For some obscure reason, the player may not have the right size on
iPad at initialization. This fix tries to fix the issue by resizing the
player when it is ready.
added ‘usesDefaultVideoRatio’ property to stretch the player to full screen when needed, better error handling
Merge commit '8f1e8284d085913c0ce65b3c89be5dbe162764cb'