Ensure that we don't add null as a toolbar

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30672 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
#3878 turn off browser autocomplete for Input Boxes

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@30677 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e