[BUGFIX] Initialize label related properties in EmulatedPageLayoutView

The new StandardContentPreviewRenderer uses an emulated PageLayoutView
for implementing "tt_content_drawItem" hooks. This patch makes sure
both the member variables $CType_labels and $itemLabels are set for
the emulated view as those properties may be accessed in a hook.

Resolves: #90598
Releases: master
Change-Id: Iec7bf473c526546587d5f762e9a5918d05d7a909
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/63503


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Oliver Bartsch <bo@cedev.de>
Tested-by: Daniel Goerz <daniel.goerz@posteo.de>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Daniel Goerz <daniel.goerz@posteo.de>