message: Add Borrow for FrozenRef<Box<T>>
diff: @@ -515,6 +515,12 @@ mod std_traits {
  }
  }
  + impl<T: ?Sized> Borrow<T> for FrozenRef<Box<T>> {
  + fn borrow(&self) -> &T {
  + &*self
  + }
  + }
  +
  impl<T: ?Sized> PartialEq for FrozenRef<T>
  where
  T: PartialEq,
  