Remove lib/dom directory!

lib/dom/templates/html/impl/impl_MutationObserver.darttemplate

-// 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.
-
-class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
-$!MEMBERS
-  void observe(Node target,
-               [Map options,
-                bool childList,
-                bool attributes,
-                bool characterData,
-                bool subtree,
-                bool attributeOldValue,
-                bool characterDataOldValue,
-                List<String> attributeFilter]) {
-
-    // Parse options into map of known type.
-    var parsedOptions = _createDict();
-
-    if (options != null) {
-      options.forEach((k, v) {
-          if (_boolKeys.containsKey(k)) {
-            _add(parsedOptions, k, true === v);
-          } else if (k == 'attributeFilter') {
-            _add(parsedOptions, k, _fixupList(v));
-          } else {
-            throw new IllegalArgumentException(
-                "Illegal MutationObserver.observe option '$k'");
-          }
-        });
-    }
-
-    // Override options passed in the map with named optional arguments.
-    override(key, value) {
-      if (value != null) _add(parsedOptions, key, value);
-    }
-
-    override('childList', childList);
-    override('attributes', attributes);
-    override('characterData', characterData);
-    override('subtree', subtree);
-    override('attributeOldValue', attributeOldValue);
-    override('characterDataOldValue', characterDataOldValue);
-    if (attributeFilter != null) {
-      override('attributeFilter', _fixupList(attributeFilter));
-    }
-
-    _call(target, parsedOptions);
-  }
-
-   // TODO: Change to a set when const Sets are available.
-  static final _boolKeys =
-    const {'childList': true,
-           'attributes': true,
-           'characterData': true,
-           'subtree': true,
-           'attributeOldValue': true,
-           'characterDataOldValue': true };
-
-$if DARTIUM
-  static _createDict() => {};
-  static _add(m, String key, value) { m[key] = value; }
-  static _fixupList(list) => list;
-
-  _call(Node target, options) {
-    _observe(target, options);
-  }
-$endif
-
-$if DART2JS
-  static _createDict() => JS('var', '{}');
-  static _add(m, String key, value) { JS('void', '#[#] = #', m, key, value); }
-  static _fixupList(list) => list;  // TODO: Ensure is a JavaScript Array.
-
-  // Call native function with no conversions.
-  _call(target, options) native 'observe';
-$endif
-}