WHEN_WITHOUT_ELSE doesn't recognize when expression in when branch

[petertrr]

Describe the bug

when (expr1) {
    is Type1 -> when (expr1.field) {
                is Type2 -> when (foo(epxr1)) {
                    SomeEnum.Field1 -> bar()
                    SomeEnum.Field2 -> baz()
                }
}

the when in is Type2 is not treated as an expression (it's treated as a statement, though it's an expression).

Expected behavior

WHEN_WITHOUT_ELSE shouldn't check when expressions at all until we have type resolution.

Environment information

• diktat version: 0.1.2

[petertrr]

Another false-positive: when expression is assigned to a var:

var x: Int
x = when () ...