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

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

Index: pkg/kernel/testcases/type-propagation/prefer_baseclass.baseline.txt
diff --git a/pkg/kernel/testcases/type-propagation/prefer_baseclass.baseline.txt b/pkg/kernel/testcases/type-propagation/prefer_baseclass.baseline.txt
deleted file mode 100644
index c54543b2657d10c2a9b5e00226f9a2c9035b5b9e..0000000000000000000000000000000000000000
--- a/pkg/kernel/testcases/type-propagation/prefer_baseclass.baseline.txt
+++ /dev/null
@@ -1,42 +0,0 @@
-library;
-import self as self;
-import "dart:core" as core;
-
-class A extends core::Object {
-  constructor •() → void
-    : super core::Object::•()
-    ;
-}
-class B extends core::Object {
-  constructor •() → void
-    : super core::Object::•()
-    ;
-}
-class AB1 extends self::A implements self::B {
-  constructor •() → void
-    : super self::A::•()
-    ;
-}
-class AB2 extends self::A implements self::B {
-  constructor •() → void
-    : super self::A::•()
-    ;
-}
-class BA1 extends self::B implements self::A {
-  constructor •() → void
-    : super self::B::•()
-    ;
-}
-class BA2 extends self::B implements self::A {
-  constructor •() → void
-    : super self::B::•()
-    ;
-}
-static method takeSubclassOfA(dynamic/self::A+ {other} obj) → dynamic/Null {}
-static method takeSubclassOfB(dynamic/self::B+ {other} obj) → dynamic/Null {}
-static method main() → dynamic/Null {
-  self::takeSubclassOfA(new self::AB1::•());
-  self::takeSubclassOfA(new self::AB2::•());
-  self::takeSubclassOfB(new self::BA1::•());
-  self::takeSubclassOfB(new self::BA2::•());
-}