Check in codegen test expectations.

test/codegen/expect/corelib/queue_single_test.js

+dart_library.library('corelib/queue_single_test', null, /* Imports */[
+  'dart_sdk',
+  'expect'
+], function load__queue_single_test(exports, dart_sdk, expect) {
+  'use strict';
+  const core = dart_sdk.core;
+  const collection = dart_sdk.collection;
+  const dart = dart_sdk.dart;
+  const dartx = dart_sdk.dartx;
+  const expect$ = expect.expect;
+  const queue_single_test = Object.create(null);
+  let QueueOfint = () => (QueueOfint = dart.constFn(collection.Queue$(core.int)))();
+  let VoidTovoid = () => (VoidTovoid = dart.constFn(dart.definiteFunctionType(dart.void, [])))();
+  let dynamicTobool = () => (dynamicTobool = dart.constFn(dart.definiteFunctionType(core.bool, [dart.dynamic])))();
+  let VoidTodynamic = () => (VoidTodynamic = dart.constFn(dart.definiteFunctionType(dart.dynamic, [])))();
+  queue_single_test.main = function() {
+    let queue1 = QueueOfint().new();
+    queue1.add(42);
+    let queue2 = collection.Queue.new();
+    queue2.add(11);
+    queue2.add(12);
+    queue2.add(13);
+    let queue3 = collection.Queue.new();
+    expect$.Expect.equals(42, queue1.single);
+    expect$.Expect.throws(dart.fn(() => queue2.single, VoidTovoid()), dart.fn(e => core.StateError.is(e), dynamicTobool()));
+    expect$.Expect.throws(dart.fn(() => queue3.single, VoidTovoid()), dart.fn(e => core.StateError.is(e), dynamicTobool()));
+  };
+  dart.fn(queue_single_test.main, VoidTodynamic());
+  // Exports:
+  exports.queue_single_test = queue_single_test;
+});