Created attachment 786505 [details]
null operator

Description of problem:
It is possible to add a condition column without an operator. 

You can either do it the "right" way and select the operator "(no operator)". This makes it look like no operator was chosen yet. Or you can do it the wrong way and not select any operator at all. Either way, if you then click Apply changes, alert pops up saying that "Operator has not been selected". If you accept that, column is added.

The column added the right way is on the right in the screenshot and really has no operator in the table header.
The column added the wrong way is on the left and unfortunately has operator null.


Version-Release number of selected component (if applicable):
kie-wb 6.0 CR1


Expected results:
The wrong way to go about it isn't possible at all or results in the same as the right way.


Additional info:
In the source code, both columns behave the same:
1.	|	//from row number: 1
2.	|	rule "Row 1 gdt"
3.	|	    dialect "mvel"
4.	|	    when
5.	|	        f : Fact( )
6.	|	        f2 : Fact( )
7.	|	    then
8.	|	end