Check in codegen test expectations.

test/codegen/expect/language/multiline_strings_test.js

Index: test/codegen/expect/language/multiline_strings_test.js
diff --git a/test/codegen/expect/language/multiline_strings_test.js b/test/codegen/expect/language/multiline_strings_test.js
new file mode 100644
index 0000000000000000000000000000000000000000..78886381707d10b9adcf129b3e7250f857cb3abd
--- /dev/null
+++ b/test/codegen/expect/language/multiline_strings_test.js
@@ -0,0 +1,30 @@
+dart_library.library('language/multiline_strings_test', null, /* Imports */[
+  'dart_sdk',
+  'expect'
+], function load__multiline_strings_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 multiline_strings_test = Object.create(null);
+  let VoidTodynamic = () => (VoidTodynamic = dart.constFn(dart.definiteFunctionType(dart.dynamic, [])))();
+  multiline_strings_test.main = function() {
+    expect$.Expect.equals('foo', 'foo');
+    expect$.Expect.equals('\\\nfoo', '\\\nfoo');
+    expect$.Expect.equals('\t\nfoo', '\t\nfoo');
+    expect$.Expect.equals('foo', 'foo');
+    expect$.Expect.equals('foo', 'foo');
+    expect$.Expect.equals(' \nfoo', ' \nfoo');
+    let x = ' ';
+    expect$.Expect.equals(' \nfoo', dart.str`${x}\nfoo`);
+    expect$.Expect.equals('foo', 'foo');
+    expect$.Expect.equals('\\\\\nfoo', '\\\\\nfoo');
+    expect$.Expect.equals('\\t\nfoo', '\\t\nfoo');
+    expect$.Expect.equals('foo', 'foo');
+    expect$.Expect.equals('foo', 'foo');
+  };
+  dart.fn(multiline_strings_test.main, VoidTodynamic());
+  // Exports:
+  exports.multiline_strings_test = multiline_strings_test;
+});