[TASK] Remove the "@todo define visibility"

The "@todo Define visibility" is not very helpful because:

 * Nobody knows what breaks if changing the visibility
 * The code is flooded with todos which makes it hard
   to work with in an IDE

During ACME it was decided to remove the @todo again.

Resolves: #61957
Releases: master
Change-Id: I0caa9756bba326dc132b6a2dabe79218c53a32c8
Reviewed-on: http://review.typo3.org/33044
Reviewed-by: Markus Klein <klein.t3@reelworx.at>
Tested-by: Markus Klein <klein.t3@reelworx.at>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>