[cas] fix for #3335, expression gives Circular definition error

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@27077 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
[27075] change fix

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@27078 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e