Fix sizing in QGraphicsView itemsAtPosition auto test

The auto test may fail incorrectly depending on the width of the
QGraphicsView frame. To ensure more consistent test results, the frame is
disabled.

Change-Id: I8d70fb07e45803230954f776947d525e4cf9050f
Reviewed-by: Robin Burchell <robin+qt@viroteck.net>

tests/auto/widgets/graphicsview/qgraphicsview/tst_qgraphicsview.cpp

@@ -1397,6 +1397,7 @@ void tst_QGraphicsView::itemsAtPosition()
         item->setFlag(QGraphicsItem::ItemIgnoresTransformations);
 
     QGraphicsView view;
+    view.setFrameStyle(QFrame::NoFrame);
     view.resize(200, 200);
     view.scale(scale, scale);
     view.rotate(rotation);