[Test Scenario] No effects when assigning a not-expression Simple Type column to expression type (and viceversa)

Step to reproduce:

• Create a new Test Scenario (RULE)
• Form "Data Object" tab, add any Java class available. (eg. Integer)
• Add the Integer > value property in the grid
• Try to re-assign the same column to an expression, selecting "Integer" class in the Test Tools.
• Nothing happens
• (the same occurs if you assign the expression first and then reassign it with Integer > value.