[BUGFIX] Fix 'Transfer selection to clipboard' button

This patch reintroduces the onclick event if the function call has no
warning. This fixes the error with the not working 'Transfer selection
to clipboard' button in the list view, if the user enables every clipboard
but the normal.

Resolves: #74122
Releases: master, 7.6
Change-Id: Iaf133951fa6278778bb468eca601185844f19130
Reviewed-on: https://review.typo3.org/47030


Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Eugen Lang <eugen.lang@werkraum.net>
Tested-by: Eugen Lang <eugen.lang@werkraum.net>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>