Check in codegen test expectations.

test/codegen/expect/language/override_inheritance_abstract_test_18_multi.js

+dart_library.library('language/override_inheritance_abstract_test_18_multi', null, /* Imports */[
+  'dart_sdk'
+], function load__override_inheritance_abstract_test_18_multi(exports, dart_sdk) {
+  'use strict';
+  const core = dart_sdk.core;
+  const dart = dart_sdk.dart;
+  const dartx = dart_sdk.dartx;
+  const override_inheritance_abstract_test_18_multi = Object.create(null);
+  let VoidTodynamic = () => (VoidTodynamic = dart.constFn(dart.definiteFunctionType(dart.dynamic, [])))();
+  override_inheritance_abstract_test_18_multi.A = class A extends core.Object {
+    method18() {}
+  };
+  dart.setSignature(override_inheritance_abstract_test_18_multi.A, {
+    methods: () => ({method18: dart.definiteFunctionType(dart.dynamic, [])})
+  });
+  override_inheritance_abstract_test_18_multi.I = class I extends core.Object {
+    method18() {}
+  };
+  dart.setSignature(override_inheritance_abstract_test_18_multi.I, {
+    methods: () => ({method18: dart.definiteFunctionType(dart.dynamic, [])})
+  });
+  override_inheritance_abstract_test_18_multi.J = class J extends core.Object {};
+  override_inheritance_abstract_test_18_multi.Class = class Class extends override_inheritance_abstract_test_18_multi.A {};
+  override_inheritance_abstract_test_18_multi.Class[dart.implements] = () => [override_inheritance_abstract_test_18_multi.I, override_inheritance_abstract_test_18_multi.J];
+  override_inheritance_abstract_test_18_multi.main = function() {
+    new override_inheritance_abstract_test_18_multi.Class();
+  };
+  dart.fn(override_inheritance_abstract_test_18_multi.main, VoidTodynamic());
+  // Exports:
+  exports.override_inheritance_abstract_test_18_multi = override_inheritance_abstract_test_18_multi;
+});