[TASK] Use name-resolution instead of strings where possible: 14

(part for extensions starting with "w")

Use name-resolution with ...::class instead of strings where
possible.
(needs PHP 5.5, which is meanwhile required for master)

Change-set Iedbb896607adddce2b23ab67f990fa2296c0d1bb
first introduced usage of ::class in master. We now add it
in various more places.

Change-Id: I60f118a60fc1784ccd83f8f86cdbb6e60b0cfc1b
Resolves: #63477
Releases: master
Reviewed-on: http://review.typo3.org/34870
Reviewed-by: Markus Klein <klein.t3@reelworx.at>
Tested-by: Markus Klein <klein.t3@reelworx.at>
Reviewed-by: Stefan Neufeind <typo3.neufeind@speedpartner.de>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>