#3026 fix for serializing (a,b,c) to CAS

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@31020 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
4.9.237.0

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@31022 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e