... setting a control's background color has no effect (until input
field text is changed?)

Could be observed in the pivot table dialog's source range edit when an
invalid range was entered.

Change-Id: Iafb2a9016ac6bd4c020273911d62dd7423ee0458
(cherry picked from commit 01a93d34)
Reviewed-on: https://gerrit.libreoffice.org/19354Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>