Re-enable debugger autotests on Mac

Partially revert 8ed38c70 to also test qqmlprofiler, qqmlinspector
on Mac. The tests were unreliable before, but that was fixed with 816e7f11f
in qtbase.

Change-Id: Icca7ff6617ea18d069d4cd95905d76fe59b92e31
Reviewed-by: Aurindam Jana <aurindam.jana@digia.com>
Avoid crash when a QML signal is connected to a non-void slot

Don't pass a QVariant pointer for the return value when we're
not interested in it and the return type might not even be a
QVariant (that would be only true for QML methods).

Task-number: QTBUG-32801
Change-Id: I8f14e40d8f94caef7e3d086b776735f0484dbf0e
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>