Check in codegen test expectations.

test/codegen/expect/corelib/list_to_string2_test.js

Index: test/codegen/expect/corelib/list_to_string2_test.js
diff --git a/test/codegen/expect/corelib/list_to_string2_test.js b/test/codegen/expect/corelib/list_to_string2_test.js
new file mode 100644
index 0000000000000000000000000000000000000000..782005a05b9a052b1b1823f933add6026a892ee3
--- /dev/null
+++ b/test/codegen/expect/corelib/list_to_string2_test.js
@@ -0,0 +1,39 @@
+dart_library.library('corelib/list_to_string2_test', null, /* Imports */[
+  'dart_sdk',
+  'expect'
+], function load__list_to_string2_test(exports, dart_sdk, expect) {
+  'use strict';
+  const core = dart_sdk.core;
+  const _interceptors = dart_sdk._interceptors;
+  const dart = dart_sdk.dart;
+  const dartx = dart_sdk.dartx;
+  const expect$ = expect.expect;
+  const list_to_string2_test = Object.create(null);
+  let JSArrayOfint = () => (JSArrayOfint = dart.constFn(_interceptors.JSArray$(core.int)))();
+  let JSArrayOfObject = () => (JSArrayOfObject = dart.constFn(_interceptors.JSArray$(core.Object)))();
+  let dynamicTobool = () => (dynamicTobool = dart.constFn(dart.definiteFunctionType(core.bool, [dart.dynamic])))();
+  let VoidTodynamic = () => (VoidTodynamic = dart.constFn(dart.definiteFunctionType(dart.dynamic, [])))();
+  list_to_string2_test.main = function() {
+    let list = JSArrayOfint().of([1, 2]);
+    list[dartx.add](list);
+    let list2 = core.List.new(4);
+    list2[dartx.set](0, 1);
+    list2[dartx.set](1, 2);
+    list2[dartx.set](2, list2);
+    list2[dartx.set](3, list);
+    expect$.Expect.equals("[1, 2, [...]]", dart.toString(list));
+    expect$.Expect.equals("[1, 2, [...], [1, 2, [...]]]", dart.toString(list2));
+    let list3 = JSArrayOfObject().of([1, 2, new list_to_string2_test.ThrowOnToString(), 4]);
+    expect$.Expect.throws(dart.bind(list3, 'toString', dart.toString), dart.fn(e => dart.equals(e, "Bad!"), dynamicTobool()));
+    list3[dartx.set](2, 3);
+    expect$.Expect.equals("[1, 2, 3, 4]", dart.toString(list3));
+  };
+  dart.fn(list_to_string2_test.main, VoidTodynamic());
+  list_to_string2_test.ThrowOnToString = class ThrowOnToString extends core.Object {
+    toString() {
+      dart.throw("Bad!");
+    }
+  };
+  // Exports:
+  exports.list_to_string2_test = list_to_string2_test;
+});