Fix crash when combining QOpenGLWidget, QStaticText and Qt Quick

Under certain circumstances, if you had a widget with a QOpenGLPaintEngine,
and drew QStaticText into this, and then later had Qt Quick access the same
cache and try to resize it, we would get a crash because the resize function
would have a pointer to the paint engine and try to access its shader manager
(which would now be null, since this is outside the begin()/end() phase of the
paint engine.

The solution is to reset the paint engine pointer to null on the cache once it
has been populated and it is no longer needed.

[ChangeLog][QtGui][Text] Fixed a possible crash when combining QStaticText,
QOpenGLWidget and Qt Quick in the same application.

Task-number: QTBUG-70096
Change-Id: I7383ad7456d1a72499cfcd2da09a5a808d4b3eff
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

0 files changed, 0 insertions, 0 deletions