webapp/sagews: sometimes, when printing threejs the scene data is not defined -- in print_to_pdf_data: TypeError: Cannot read property "set_static_renderer" of undefined
webapp/sagews: sometimes, when printing threejs the scene data is not defined -- in print_to_pdf_data: TypeError: Cannot read property "set_static_renderer" of undefined

tscholl2/smc,sagemathinc/smc,DrXyzzy/smc,sagemathinc/smc,sagemathinc/smc,DrXyzzy/smc,DrXyzzy/smc,tscholl2/smc,DrXyzzy/smc,tscholl2/smc,tscholl2/smc,tscholl2/smc,sagemathinc/smc