Crash when selecting text in a QTextEdit or QTextBrowser ( RC: ou1cimx1#491113)

Selecting text in a QTextEdit or QTextBrowser when rendering with the OpenVG graphics system results in a crash. The root of the problem is clipping with a null path and when text is selected in one of the above widgets, the rendering path will use a null path clip. The OpenVG paint engine crashes when a null clip is used.

Text selection is *not * the only way to reproduce this bug though. Any widget that paints content and happens to use a null clip path will immediately cause a crash. WebKit is the biggest user of path clipping in Qt so it is possible that a null path clip code path could be hit there as well.