Check in codegen test expectations.

test/codegen/expect/lib/convert/utf85_test.js

+dart_library.library('lib/convert/utf85_test', null, /* Imports */[
+  'dart_sdk',
+  'expect'
+], function load__utf85_test(exports, dart_sdk, expect) {
+  'use strict';
+  const core = dart_sdk.core;
+  const convert = dart_sdk.convert;
+  const dart = dart_sdk.dart;
+  const dartx = dart_sdk.dartx;
+  const expect$ = expect.expect;
+  const utf85_test = Object.create(null);
+  let VoidTodynamic = () => (VoidTodynamic = dart.constFn(dart.definiteFunctionType(dart.dynamic, [])))();
+  utf85_test.main = function() {
+    for (let i = 0; i <= 1114111; i++) {
+      if (i == convert.UNICODE_BOM_CHARACTER_RUNE) continue;
+      expect$.Expect.equals(i, convert.UTF8.decode(convert.UTF8.encode(core.String.fromCharCode(i)))[dartx.runes].first);
+    }
+  };
+  dart.fn(utf85_test.main, VoidTodynamic());
+  // Exports:
+  exports.utf85_test = utf85_test;
+});