Inferred override type of final val

[som-snytt]

Reproduction steps

Scala version: 2.13.12

➜  snips cat narrows.scala

class C {
  def i: Int = 42
}
object D extends C {
  override final val i = 27
}
object Test {
  def f: 27 = D.i
}

Problem

Compiles under 2.13 but not under -Xsource:3 because of the inferred type for D.i.

Dotty correctly infers 27. Probably Scala 2 inadvertently widens when picking the "narrow" intersection.

Noticed at https://github.com/scala/scala/pull/10439#issuecomment-1637074874