[Refactoring] Add findGotoTarget to share common code
[Refactoring] Return NULL from WithStatement::interpret()
[Refactoring] Remove Statement::interpret()
[Refactoring] Remove Expression::interpret()
[Refactoring] Handle NULL Expression or Statement in interpret() call
Merge pull request #4170 from 9rnsr/refactor_ctfe

[Refactoring] Remove interpret member function from Expression and Statement