Added minimal documentation to the KeyboardEvent class.

sdk/lib/html/dart2js/html_dart2js.dart

 /// The Dart HTML library.
 library dart.dom.html;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:_collection-dev' hide Symbol;
 import 'dart:html_common';
 import 'dart:indexed_db';
 import 'dart:isolate';
 import 'dart:json' as json;
@@ skipping 13439 matching lines @@
 
   @DomName('InputMethodContext.setExclusionRectangle')
   @DocsEditable
   void setExclusionRectangle(Node anchor, int x, int y, int w, int h) native;
 }
 // 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.
 
 
+/**
+ * An event that describes user interaction with the keyboard.
+ *
+ * The [type] of the event identifies what kind of interaction occurred.
+ *
+ * See also:
+ *
+ * * [KeyboardEvent](https://developer.mozilla.org/en/DOM/KeyboardEvent) at MDN.
+ */
 @DomName('KeyboardEvent')
 class KeyboardEvent extends UIEvent native "KeyboardEvent" {
 
   factory KeyboardEvent(String type,
       {Window view, bool canBubble: true, bool cancelable: true,
       String keyIdentifier: "", int keyLocation: 1, bool ctrlKey: false,
       bool altKey: false, bool shiftKey: false, bool metaKey: false,
       bool altGraphKey: false}) {
     if (view == null) {
       view = window;
@@ skipping 16135 matching lines @@
       _position = nextPosition;
       return true;
     }
     _current = null;
     _position = _array.length;
     return false;
   }
 
   T get current => _current;
 }