Description of problem:

If you use a Free Form DRL in a Guided Editor which includes call of a setter method with multiple parameters after saving and refreshing such a rule Guided Editor simply "breaks it".

You are probably asking why would I setter method with multiple parameters, but one real use case is to call WorkflowProcessInstance.setVariable("param","value")

Version-Release number of selected component (if applicable):

BPM 6.0.2
How reproducible:
always

Steps to Reproduce:
1. Create Guided rule, with free form DRL in the RHS. Make sure there is call of a sether method which includes multiple params
2. save the rule, refresh the page
3. open the rule again, type something in the setter field
4. save the rule again

Following exception is displayed:

17:03:53,400 ERROR [org.drools.compiler.kie.builder.impl.AbstractKieModule] (EJB default - 4) Unable to build KieBaseModel:defaultKieBase
Unable to Analyse Expression $process.setVariable( "5ne\",\"two" );:
[Error: unable to resolve method using strict-mode: org.kie.api.runtime.process.WorkflowProcessInstance.setVariable(java.lang.String)]
[Near :

]
^
[Line: 3, Column: 0] : [Rule name='sampleRule']

Actual results:

Guided Editor is not able to cope with the Free Form DRL which includes call of a setter method with multiple parameters
Expected results: