Check in codegen test expectations.

test/codegen/expect/corelib/regexp/default_arguments_test.js

+dart_library.library('corelib/regexp/default_arguments_test', null, /* Imports */[
+  'dart_sdk',
+  'expect'
+], function load__default_arguments_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 default_arguments_test = Object.create(null);
+  let VoidTodynamic = () => (VoidTodynamic = dart.constFn(dart.definiteFunctionType(dart.dynamic, [])))();
+  default_arguments_test.main = function() {
+    default_arguments_test.testCaseSensitive();
+    default_arguments_test.testMultiLine();
+  };
+  dart.fn(default_arguments_test.main, VoidTodynamic());
+  default_arguments_test.testCaseSensitive = function() {
+    let r1 = core.RegExp.new('foo');
+    let r2 = core.RegExp.new('foo', {caseSensitive: true});
+    let r3 = core.RegExp.new('foo', {caseSensitive: false});
+    let r4 = core.RegExp.new('foo', {caseSensitive: null});
+    expect$.Expect.isNull(r1.firstMatch('Foo'), "r1.firstMatch('Foo')");
+    expect$.Expect.isNull(r2.firstMatch('Foo'), "r2.firstMatch('Foo')");
+    expect$.Expect.isNotNull(r3.firstMatch('Foo'), "r3.firstMatch('Foo')");
+    expect$.Expect.isNotNull(r4.firstMatch('Foo'), "r4.firstMatch('Foo')");
+  };
+  dart.fn(default_arguments_test.testCaseSensitive, VoidTodynamic());
+  default_arguments_test.testMultiLine = function() {
+    let r1 = core.RegExp.new('^foo$');
+    let r2 = core.RegExp.new('^foo$', {multiLine: true});
+    let r3 = core.RegExp.new('^foo$', {multiLine: false});
+    let r4 = core.RegExp.new('^foo$', {multiLine: null});
+    expect$.Expect.isNull(r1.firstMatch('\nfoo\n'), "r1.firstMatch('\\nfoo\\n')");
+    expect$.Expect.isNotNull(r2.firstMatch('\nfoo\n'), "r2.firstMatch('\\nfoo\\n')");
+    expect$.Expect.isNull(r3.firstMatch('\nfoo\n'), "r3.firstMatch('\\nfoo\\n')");
+    expect$.Expect.isNull(r4.firstMatch('\nfoo\n'), "r4.firstMatch('\\nfoo\\n')");
+  };
+  dart.fn(default_arguments_test.testMultiLine, VoidTodynamic());
+  // Exports:
+  exports.default_arguments_test = default_arguments_test;
+});