Merged requested to merge nicolasfella/qtbase:work/nico/QTBUG-104917 into kde/5.15
Drawing PE_PanelLineEdit in QStyleSheetStyle with the default argument widget = nullptr causes a segfault.
drawPrimitive tries to fall back to a container widget's render rule and therefore calls containerWidget() - which crashes when called with nullptr.
Container widget fallback is pointless when drawPrimitive() is called with widget == nullptr. This patch skips it in that case.
Fixes: QTBUG-104917 Pick-to: 6.4 6.3 6.2 Change-Id: I09e57dccfebb81a308944c233846d5b9ef58819e Reviewed-by: Volker Hilsheimer firstname.lastname@example.org (cherry picked from commit effc8be3)