Check in codegen test expectations.

test/codegen/expect/language/context_args_with_defaults_test.js

+dart_library.library('language/context_args_with_defaults_test', null, /* Imports */[
+  'dart_sdk',
+  'expect'
+], function load__context_args_with_defaults_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 context_args_with_defaults_test = Object.create(null);
+  let VoidTodynamic = () => (VoidTodynamic = dart.constFn(dart.definiteFunctionType(dart.dynamic, [])))();
+  context_args_with_defaults_test.ContextArgsWithDefaultsTest = class ContextArgsWithDefaultsTest extends core.Object {
+    static testMain() {
+      dart.dcall(context_args_with_defaults_test.ContextArgsWithDefaultsTest.crasher(1, 'foo'));
+    }
+    static crasher(fixed, optional) {
+      if (optional === void 0) optional = '';
+      return dart.fn(() => {
+        expect$.Expect.equals(1, fixed);
+        expect$.Expect.equals('foo', optional);
+      }, VoidTodynamic());
+    }
+  };
+  dart.setSignature(context_args_with_defaults_test.ContextArgsWithDefaultsTest, {
+    statics: () => ({
+      testMain: dart.definiteFunctionType(dart.void, []),
+      crasher: dart.definiteFunctionType(dart.dynamic, [core.int], [core.String])
+    }),
+    names: ['testMain', 'crasher']
+  });
+  context_args_with_defaults_test.main = function() {
+    context_args_with_defaults_test.ContextArgsWithDefaultsTest.testMain();
+  };
+  dart.fn(context_args_with_defaults_test.main, VoidTodynamic());
+  // Exports:
+  exports.context_args_with_defaults_test = context_args_with_defaults_test;
+});