[omxplayer] merge missed commits from dvdplayer

I've just had a look at the diffs between latest dvdplayer and omxplayer and found 4 commits that have been unintentionally missed from omxplayer.

They all looks like they should be present, and keeping the two files in sync helps future merges of patches.

These are the original commits:
https://github.com/xbmc/xbmc/commit/835fa9f80ae212dae24a10a5979656189a5c9e7f
https://github.com/xbmc/xbmc/commit/44cca8be3f195835b83964ecfd7ac0cae2aa73c3
https://github.com/xbmc/xbmc/commit/ea0ee2f50c924b03d078a36dd64b6178e228fc61
https://github.com/xbmc/xbmc/commit/4d6fe6663298923175424d1dc199476a774cf3e2