fix init for clients who haven't XFlush'd yet
fix init for clients who haven't XFlush'd yet

lunixbochs/glshim,seandepagnier/glshim,RobertoMalatesta/glshim,RobertoMalatesta/glshim,seandepagnier/glshim,seandepagnier/glshim,RobertoMalatesta/glshim,RobertoMalatesta/glshim,lunixbochs/glshim,lunixbochs/glshim,seandepagnier/glshim,lunixbochs/glshim