From Ed Ralston, "According to the OSX Developer Documentation, CFRelease cannot be called with a NULL argument.
From Ed Ralston, "According to the OSX Developer Documentation, CFRelease
cannot be called with a NULL argument.

This patch prevents osgDB::FileUtils from doing this."


openscenegraph/osg,jtorresfabra/osg,tomasthoresen/osg,artoolkit/osg,marchelbling/osg,marchelbling/osg,openscenegraph/osg,tomasthoresen/osg,scrawl/osg,jtorresfabra/osg,artoolkit/osg,tomasthoresen/osg,artoolkit/osg,marchelbling/osg,scrawl/osg,jtorresfabra/osg,jtorresfabra/osg,scrawl/osg,openscenegraph/osg,marchelbling/osg,tomasthoresen/osg,scrawl/osg,artoolkit/osg,openscenegraph/osg