Cleanup references to the old DDC repo

pkg/dev_compiler/tool/input_sdk/private/ddc_runtime/utils.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 part of dart._runtime;
 
 /// This library defines a set of general javascript utilities for us
 /// by the Dart runtime.
 // TODO(ochafik): Rewrite some of these in Dart when possible.
 
 defineProperty(obj, name, desc) =>
@@ skipping 80 matching lines @@
   }
   return $to;
 })()''');
 
 copyProperty(to, from, name) {
   var desc = getOwnPropertyDescriptor(from, name);
   if (JS('bool', '# == Symbol.iterator', name)) {
     // On native types, Symbol.iterator may already be present.
     // TODO(jmesserly): investigate if we still need this.
     // If so, we need to find a better solution.
-    // See: https://github.com/dart-lang/dev_compiler/issues/487
+    // See https://github.com/dart-lang/sdk/issues/28324
     var existing = getOwnPropertyDescriptor(to, name);
     if (existing != null) {
       if (JS('bool', '#.writable', existing)) {
         JS('', '#[#] = #.value', to, name, desc);
       }
       return;
     }
   }
   defineProperty(to, name, desc);
 }
 
 @JSExportName('export')
 exportProperty(to, from, name) => copyProperty(to, from, name);
 
 /// Copy properties from source to destination object.
 /// This operation is commonly called `mixin` in JS.
 copyProperties(to, from) {
   return copyTheseProperties(to, from, getOwnNamesAndSymbols(from));
 }