[CLEANUP] #4320 Add @var type hinting

Change-Id: I5a4e96ab5d8429272926524b649670506ea86632
Reviewed-on: http://review.typo3.org/35331
Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Tested-by: Oliver Klee <typo3-coding@oliverklee.de>