BZ1127303: Guided Editor breaks free form DRL which includes setter method with multi parameters

(cherry picked from commit c9a56fedf854c59ff940f716c478a5ae7c68ad16)
GUVNOR-2144: Guided rule editor: String index out of range: -1

(cherry picked from commit 195d02587f089e834ef337a5ce830a075942ce90)