The previous fix a05270f435 is not correct,
QPainterPathPrivate(other) should be QPainterPathPrivate(), as there
is only a default ctor for QPainterPathPrivate and ref is initialized there,
use copy ctor just copies the ref value which makes all detach() calls broken.
Add an unit test for this as well.
Change-Id: I658f0a977664d5ec523af3f8a48c1a866eda6ab0
Reviewed-by: Martin Jones <martin.jones@nokia.com>
78542c6275