[Qt] Temporarily disable use of QXcbNativeInterface in GraphicsSurfaceGLX.
Once QXcbNativeInterface::nativeResourceForContext() can provide the GLXContext for an existing QOpenGLContext, this patch shall be reverted. The patch required for this, is currently staging in the Qt CI.
Created attachment 170887 [details] Patch
Committed r132629: <http://trac.webkit.org/changeset/132629>