[TASK] Use fully qualified name resolution in PHP 5.5

Since PHP 5.5 is a requirement, calls with the objectManager
should use the ::class construct instead of a string argument.

Resolves: #63112
Releases: master
Change-Id: Iedbb896607adddce2b23ab67f990fa2296c0d1bb
Reviewed-on: http://review.typo3.org/34414
Reviewed-by: Markus Klein <klein.t3@reelworx.at>
Tested-by: Markus Klein <klein.t3@reelworx.at>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>