Remove some additional code that depended on the old type propagation.

pkg/kernel/testcases/type-propagation/closure.baseline.txt

-library;
-import self as self;
-import "dart:core" as core;
-
-class Foo extends core::Object {
-  field dynamic/self::Bar! {other} _field = new self::Bar::•();
-  constructor •() → void
-    : super core::Object::•()
-    ;
-}
-class Bar extends core::Object {
-  constructor •() → void
-    : super core::Object::•()
-    ;
-}
-static method useCallback(dynamic/core::Function* {other} callback) → dynamic/Null {
-  dynamic/self::Foo! {other} _ = callback.call();
-}
-static method main() → dynamic/Null {
-  dynamic/self::Foo! {null,other} x;
-  function inner() → dynamic/self::Foo! {other} {
-    x = new self::Foo::•();
-    return new self::Foo::•();
-  }
-  self::useCallback(inner);
-  dynamic/self::Bar! {other} _ = inner.call()._field;
-}