[SECURITY] XSS in 3rd party library Flowplayer

Change-Id: I6bb53b23ca4df6f8d4b8ee801bd99a1a5c32f5b2
Fixes: #49209
Releases: 4.7, 6.0, 6.1, 6.2
Security-Commit: 7d306dbb20eb3a6b1dbee6c9896835c50dda87eb
Security-Bulletin: TYPO3-CORE-SA-2013-002
Reviewed-on: https://review.typo3.org/22711
Reviewed-by: Oliver Hader
Tested-by: Oliver Hader