Change /// @docsEditable to @DocsEditable annotation.

sdk/lib/html/html_common/metadata.dart

 // Copyright (c) 2012, 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.
 
 library metadata;
 
 /**
  * An annotation used to mark a feature as only being supported by a subset
  * of the browsers that Dart supports by default.
  *
@@ skipping 36 matching lines @@
  * Metadata that specifies the DOM name associated with the element.
  *
  * This is used for API generation.
  *
  * [name] should be formatted as `interface.member`.
  */
 class DomName {
   final String name;
   const DomName(this.name);
 }
+
+
+/// Metadata that specifies that that member is editable through generated
+/// files.
+class DocsEditable {
+  const DocsEditable();
+}