Check in codegen test expectations.

test/codegen/expect/language/mixin_this_use_test.js

Index: test/codegen/expect/language/mixin_this_use_test.js
diff --git a/test/codegen/expect/language/mixin_this_use_test.js b/test/codegen/expect/language/mixin_this_use_test.js
new file mode 100644
index 0000000000000000000000000000000000000000..62988229f6eb730ce58e57145c83e5e3be912c66
--- /dev/null
+++ b/test/codegen/expect/language/mixin_this_use_test.js
@@ -0,0 +1,49 @@
+dart_library.library('language/mixin_this_use_test', null, /* Imports */[
+  'dart_sdk',
+  'expect'
+], function load__mixin_this_use_test(exports, dart_sdk, expect) {
+  'use strict';
+  const core = dart_sdk.core;
+  const dart = dart_sdk.dart;
+  const dartx = dart_sdk.dartx;
+  const expect$ = expect.expect;
+  const mixin_this_use_test = Object.create(null);
+  let VoidTodynamic = () => (VoidTodynamic = dart.constFn(dart.definiteFunctionType(dart.dynamic, [])))();
+  mixin_this_use_test.A = class A extends core.Object {
+    foo() {
+      return this.bar();
+    }
+    bar() {
+      return 42;
+    }
+  };
+  dart.setSignature(mixin_this_use_test.A, {
+    methods: () => ({
+      foo: dart.definiteFunctionType(dart.dynamic, []),
+      bar: dart.definiteFunctionType(dart.dynamic, [])
+    })
+  });
+  mixin_this_use_test.B = class B extends core.Object {};
+  mixin_this_use_test.C = class C extends dart.mixin(mixin_this_use_test.B, mixin_this_use_test.A) {
+    new() {
+      super.new();
+    }
+  };
+  mixin_this_use_test.D = class D extends mixin_this_use_test.C {
+    bar() {
+      return 54;
+    }
+  };
+  mixin_this_use_test.E = class E extends mixin_this_use_test.A {
+    bar() {
+      return 68;
+    }
+  };
+  mixin_this_use_test.main = function() {
+    expect$.Expect.equals(54, new mixin_this_use_test.D().foo());
+    expect$.Expect.equals(68, new mixin_this_use_test.E().foo());
+  };
+  dart.fn(mixin_this_use_test.main, VoidTodynamic());
+  // Exports:
+  exports.mixin_this_use_test = mixin_this_use_test;
+});