Check in codegen test expectations.

test/codegen/expect/corelib/date_time2_test.js

Index: test/codegen/expect/corelib/date_time2_test.js
diff --git a/test/codegen/expect/corelib/date_time2_test.js b/test/codegen/expect/corelib/date_time2_test.js
new file mode 100644
index 0000000000000000000000000000000000000000..fb1b00edc22278d5f8e64971c6ad5e38d0294bb3
--- /dev/null
+++ b/test/codegen/expect/corelib/date_time2_test.js
@@ -0,0 +1,20 @@
+dart_library.library('corelib/date_time2_test', null, /* Imports */[
+  'dart_sdk',
+  'expect'
+], function load__date_time2_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 date_time2_test = Object.create(null);
+  let VoidTodynamic = () => (VoidTodynamic = dart.constFn(dart.definiteFunctionType(dart.dynamic, [])))();
+  date_time2_test.main = function() {
+    let d = core.DateTime.parse("2000-01-01T00:00:00Z");
+    let d2 = core.DateTime.parse("2000-01-01T00:00:01Z");
+    expect$.Expect.isFalse(dart.hashCode(d) == dart.hashCode(d2));
+  };
+  dart.fn(date_time2_test.main, VoidTodynamic());
+  // Exports:
+  exports.date_time2_test = date_time2_test;
+});