Move kernel baseline tests to front_end.

pkg/front_end/test/fasta/rasta/issue_000081.dart.direct.expect

-library;
-import self as self;
-import "dart:core" as core;
-
-class Base extends core::Object {
-  field core::int hashCode = 42;
-  constructor •() → void
-    : super core::Object::•()
-    ;
-}
-class Sub extends self::Base {
-  field core::int _hashCode = null;
-  constructor •() → void
-    : super self::Base::•()
-    ;
-  get hashCode() → dynamic
-    return let final dynamic #t1 = this._hashCode in #t1.==(null) ? this._hashCode = this.{=self::Base::hashCode} : #t1;
-  method foo() → dynamic {
-    this._hashCode.==(null) ? this._hashCode = this.{=self::Base::hashCode} : null;
-  }
-}
-static method main() → dynamic {
-  core::print(new self::Sub::•().hashCode);
-  dynamic l = <dynamic>[null];
-  let final dynamic #t2 = l in let final dynamic #t3 = 0 in #t2.[](#t3).==(null) ? #t2.[]=(#t3, "fisk") : null;
-}