Pull args, intl, logging, shelf, and source_maps out of the SDK.

pkg/third_party/html5lib/lib/dom.dart

Index: pkg/third_party/html5lib/lib/dom.dart
diff --git a/pkg/third_party/html5lib/lib/dom.dart b/pkg/third_party/html5lib/lib/dom.dart
deleted file mode 100644
index 3c5b332911444c43719e9f463946a2040f16b6e0..0000000000000000000000000000000000000000
--- a/pkg/third_party/html5lib/lib/dom.dart
+++ /dev/null
@@ -1,1020 +0,0 @@
-/// A simple tree API that results from parsing html. Intended to be compatible
-/// with dart:html, but it is missing many types and APIs.
-library dom;
-
-// TODO(jmesserly): lots to do here. Originally I wanted to generate this using
-// our Blink IDL generator, but another idea is to directly use the excellent
-// http://dom.spec.whatwg.org/ and http://html.spec.whatwg.org/ and just
-// implement that.
-
-import 'dart:collection';
-import 'package:source_span/source_span.dart';
-
-import 'src/constants.dart';
-import 'src/css_class_set.dart';
-import 'src/list_proxy.dart';
-import 'src/query_selector.dart' as query;
-import 'src/token.dart';
-import 'src/tokenizer.dart';
-import 'dom_parsing.dart';
-import 'parser.dart';
-
-export 'src/css_class_set.dart' show CssClassSet;
-
-// TODO(jmesserly): this needs to be replaced by an AttributeMap for attributes
-// that exposes namespace info.
-class AttributeName implements Comparable {
-  /// The namespace prefix, e.g. `xlink`.
-  final String prefix;
-
-  /// The attribute name, e.g. `title`.
-  final String name;
-
-  /// The namespace url, e.g. `http://www.w3.org/1999/xlink`
-  final String namespace;
-
-  const AttributeName(this.prefix, this.name, this.namespace);
-
-  String toString() {
-    // Implement:
-    // http://www.whatwg.org/specs/web-apps/current-work/multipage/the-end.html#serializing-html-fragments
-    // If we get here we know we are xml, xmlns, or xlink, because of
-    // [HtmlParser.adjustForeignAttriubtes] is the only place we create
-    // an AttributeName.
-    return prefix != null ? '$prefix:$name' : name;
-  }
-
-  int get hashCode {
-    int h = prefix.hashCode;
-    h = 37 * (h & 0x1FFFFF) + name.hashCode;
-    h = 37 * (h & 0x1FFFFF) + namespace.hashCode;
-    return h & 0x3FFFFFFF;
-  }
-
-  int compareTo(other) {
-    // Not sure about this sort order
-    if (other is! AttributeName) return 1;
-    int cmp = (prefix != null ? prefix : "").compareTo(
-          (other.prefix != null ? other.prefix : ""));
-    if (cmp != 0) return cmp;
-    cmp = name.compareTo(other.name);
-    if (cmp != 0) return cmp;
-    return namespace.compareTo(other.namespace);
-  }
-
-  bool operator ==(x) {
-    if (x is! AttributeName) return false;
-    return prefix == x.prefix && name == x.name && namespace == x.namespace;
-  }
-}
-
-// http://dom.spec.whatwg.org/#parentnode
-abstract class _ParentNode implements Node {
-  // TODO(jmesserly): this is only a partial implementation
-
-  /// Seaches for the first descendant node matching the given selectors, using
-  /// a preorder traversal.
-  ///
-  /// NOTE: Not all selectors from
-  /// [selectors level 4](http://dev.w3.org/csswg/selectors-4/)
-  /// are implemented. For example, nth-child does not implement An+B syntax
-  /// and *-of-type is not implemented. If a selector is not implemented this
-  /// method will throw [UniplmentedError].
-  Element querySelector(String selector) =>
-      query.querySelector(this, selector);
-
-  /// Returns all descendant nodes matching the given selectors, using a
-  /// preorder traversal.
-  ///
-  /// NOTE: Not all selectors from
-  /// [selectors level 4](http://dev.w3.org/csswg/selectors-4/)
-  /// are implemented. For example, nth-child does not implement An+B syntax
-  /// and *-of-type is not implemented. If a selector is not implemented this
-  /// method will throw [UniplmentedError].
-  List<Element> querySelectorAll(String selector) =>
-      query.querySelectorAll(this, selector);
-}
-
-// http://dom.spec.whatwg.org/#interface-nonelementparentnode
-abstract class _NonElementParentNode implements _ParentNode {
-  // TODO(jmesserly): could be faster, should throw on invalid id.
-  Element getElementById(String id) => querySelector('#$id');
-}
-
-// This doesn't exist as an interface in the spec, but it's useful to merge
-// common methods from these:
-// http://dom.spec.whatwg.org/#interface-document
-// http://dom.spec.whatwg.org/#element
-abstract class _ElementAndDocument implements _ParentNode {
-  // TODO(jmesserly): could be faster, should throw on invalid tag/class names.
-
-  List<Element> getElementsByTagName(String localName) =>
-      querySelectorAll(localName);
-
-  List<Element> getElementsByClassName(String classNames) =>
-      querySelectorAll(classNames.splitMapJoin(' ',
-          onNonMatch: (m) => m.isNotEmpty ? '.$m' : m,
-          onMatch: (m) => ''));
-}
-
-/// Really basic implementation of a DOM-core like Node.
-abstract class Node {
-  static const int ATTRIBUTE_NODE = 2;
-  static const int CDATA_SECTION_NODE = 4;
-  static const int COMMENT_NODE = 8;
-  static const int DOCUMENT_FRAGMENT_NODE = 11;
-  static const int DOCUMENT_NODE = 9;
-  static const int DOCUMENT_TYPE_NODE = 10;
-  static const int ELEMENT_NODE = 1;
-  static const int ENTITY_NODE = 6;
-  static const int ENTITY_REFERENCE_NODE = 5;
-  static const int NOTATION_NODE = 12;
-  static const int PROCESSING_INSTRUCTION_NODE = 7;
-  static const int TEXT_NODE = 3;
-
-  /// The parent of the current node (or null for the document node).
-  Node parentNode;
-
-  /// The parent element of this node.
-  ///
-  /// Returns null if this node either does not have a parent or its parent is
-  /// not an element.
-  Element get parent => parentNode is Element ? parentNode : null;
-
-  // TODO(jmesserly): should move to Element.
-  /// A map holding name, value pairs for attributes of the node.
-  ///
-  /// Note that attribute order needs to be stable for serialization, so we use
-  /// a LinkedHashMap. Each key is a [String] or [AttributeName].
-  LinkedHashMap<dynamic, String> attributes = new LinkedHashMap();
-
-  /// A list of child nodes of the current node. This must
-  /// include all elements but not necessarily other node types.
-  final NodeList nodes = new NodeList._();
-
-  List<Element> _elements;
-
-  // TODO(jmesserly): consider using an Expando for this, and put it in
-  // dom_parsing. Need to check the performance affect.
-  /// The source span of this node, if it was created by the [HtmlParser].
-  FileSpan sourceSpan;
-
-  /// The attribute spans if requested. Otherwise null.
-  LinkedHashMap<dynamic, FileSpan> _attributeSpans;
-  LinkedHashMap<dynamic, FileSpan> _attributeValueSpans;
-
-  Node._() {
-    nodes._parent = this;
-  }
-
-  /// If [sourceSpan] is available, this contains the spans of each attribute.
-  /// The span of an attribute is the entire attribute, including the name and
-  /// quotes (if any). For example, the span of "attr" in `<a attr="value">`
-  /// would be the text `attr="value"`.
-  LinkedHashMap<dynamic, FileSpan> get attributeSpans {
-    _ensureAttributeSpans();
-    return _attributeSpans;
-  }
-
-  /// If [sourceSpan] is available, this contains the spans of each attribute's
-  /// value. Unlike [attributeSpans], this span will inlcude only the value.
-  /// For example, the value span of "attr" in `<a attr="value">` would be the
-  /// text `value`.
-  LinkedHashMap<dynamic, FileSpan> get attributeValueSpans {
-    _ensureAttributeSpans();
-    return _attributeValueSpans;
-  }
-
-  List<Element> get children {
-    if (_elements == null) {
-      _elements = new FilteredElementList(this);
-    }
-    return _elements;
-  }
-
-  /// Returns a copy of this node.
-  ///
-  /// If [deep] is `true`, then all of this node's children and decendents are
-  /// copied as well. If [deep] is `false`, then only this node is copied.
-  Node clone(bool deep);
-
-  int get nodeType;
-
-  // http://domparsing.spec.whatwg.org/#extensions-to-the-element-interface
-  String get _outerHtml {
-    var str = new StringBuffer();
-    _addOuterHtml(str);
-    return str.toString();
-  }
-
-  String get _innerHtml {
-    var str = new StringBuffer();
-    _addInnerHtml(str);
-    return str.toString();
-  }
-
-  // Implemented per: http://dom.spec.whatwg.org/#dom-node-textcontent
-  String get text => null;
-  set text(String value) {}
-
-  void append(Node node) => nodes.add(node);
-
-  Node get firstChild => nodes.isNotEmpty ? nodes[0] : null;
-
-  void _addOuterHtml(StringBuffer str);
-
-  void _addInnerHtml(StringBuffer str) {
-    for (Node child in nodes) child._addOuterHtml(str);
-  }
-
-  Node remove() {
-    // TODO(jmesserly): is parent == null an error?
-    if (parentNode != null) {
-      parentNode.nodes.remove(this);
-    }
-    return this;
-  }
-
-  /// Insert [node] as a child of the current node, before [refNode] in the
-  /// list of child nodes. Raises [UnsupportedOperationException] if [refNode]
-  /// is not a child of the current node. If refNode is null, this adds to the
-  /// end of the list.
-  void insertBefore(Node node, Node refNode) {
-    if (refNode == null) {
-      nodes.add(node);
-    } else {
-      nodes.insert(nodes.indexOf(refNode), node);
-    }
-  }
-
-  /// Replaces this node with another node.
-  Node replaceWith(Node otherNode) {
-    if (parentNode == null) {
-      throw new UnsupportedError('Node must have a parent to replace it.');
-    }
-    parentNode.nodes[parentNode.nodes.indexOf(this)] = otherNode;
-    return this;
-  }
-
-  // TODO(jmesserly): should this be a property or remove?
-  /// Return true if the node has children or text.
-  bool hasContent() => nodes.length > 0;
-
-  /// Move all the children of the current node to [newParent].
-  /// This is needed so that trees that don't store text as nodes move the
-  /// text in the correct way.
-  void reparentChildren(Node newParent) {
-    newParent.nodes.addAll(nodes);
-    nodes.clear();
-  }
-
-  bool hasChildNodes() => !nodes.isEmpty;
-
-  bool contains(Node node) => nodes.contains(node);
-
-  /// Checks if this is a type selector.
-  /// See <http://www.w3.org/TR/CSS2/grammar.html>.
-  /// Note: this doesn't support '*', the universal selector, non-ascii chars or
-  /// escape chars.
-  bool _isTypeSelector(String selector) {
-    // Parser:
-
-    // element_name
-    //   : IDENT | '*'
-    //   ;
-
-    // Lexer:
-
-    // nmstart   [_a-z]|{nonascii}|{escape}
-    // nmchar    [_a-z0-9-]|{nonascii}|{escape}
-    // ident   -?{nmstart}{nmchar}*
-    // nonascii  [\240-\377]
-    // unicode   \\{h}{1,6}(\r\n|[ \t\r\n\f])?
-    // escape    {unicode}|\\[^\r\n\f0-9a-f]
-
-    // As mentioned above, no nonascii or escape support yet.
-    int len = selector.length;
-    if (len == 0) return false;
-
-    int i = 0;
-    const int DASH = 45;
-    if (selector.codeUnitAt(i) == DASH) i++;
-
-    if (i >= len || !isLetter(selector[i])) return false;
-    i++;
-
-    for (; i < len; i++) {
-      if (!isLetterOrDigit(selector[i]) && selector.codeUnitAt(i) != DASH) {
-        return false;
-      }
-    }
-
-    return true;
-  }
-
-  /// Initialize [attributeSpans] using [sourceSpan].
-  void _ensureAttributeSpans() {
-    if (_attributeSpans != null) return;
-
-    _attributeSpans = new LinkedHashMap<dynamic, FileSpan>();
-    _attributeValueSpans = new LinkedHashMap<dynamic, FileSpan>();
-
-    if (sourceSpan == null) return;
-
-    var tokenizer = new HtmlTokenizer(sourceSpan.text, generateSpans: true,
-        attributeSpans: true);
-
-    tokenizer.moveNext();
-    var token = tokenizer.current as StartTagToken;
-
-    if (token.attributeSpans == null) return; // no attributes
-
-    for (var attr in token.attributeSpans) {
-      var offset = sourceSpan.start.offset;
-      _attributeSpans[attr.name] = sourceSpan.file.span(
-          offset + attr.start, offset + attr.end);
-      if (attr.startValue != null) {
-        _attributeValueSpans[attr.name] = sourceSpan.file.span(
-            offset + attr.startValue, offset + attr.endValue);
-      }
-    }
-  }
-
-  _clone(Node shallowClone, bool deep) {
-    if (deep) {
-      for (var child in nodes) {
-        shallowClone.append(child.clone(true));
-      }
-    }
-    return shallowClone;
-  }
-}
-
-class Document extends Node
-    with _ParentNode, _NonElementParentNode, _ElementAndDocument {
-
-  Document() : super._();
-  factory Document.html(String html) => parse(html);
-
-  int get nodeType => Node.DOCUMENT_NODE;
-
-  // TODO(jmesserly): optmize this if needed
-  Element get documentElement => querySelector('html');
-  Element get head => documentElement.querySelector('head');
-  Element get body => documentElement.querySelector('body');
-
-  /// Returns a fragment of HTML or XML that represents the element and its
-  /// contents.
-  // TODO(jmesserly): this API is not specified in:
-  // <http://domparsing.spec.whatwg.org/> nor is it in dart:html, instead
-  // only Element has outerHtml. However it is quite useful. Should we move it
-  // to dom_parsing, where we keep other custom APIs?
-  String get outerHtml => _outerHtml;
-
-  String toString() => "#document";
-
-  void _addOuterHtml(StringBuffer str) => _addInnerHtml(str);
-
-  Document clone(bool deep) => _clone(new Document(), deep);
-
-  Element createElement(String tag) => new Element.tag(tag);
-
-  // TODO(jmesserly): this is only a partial implementation of:
-  // http://dom.spec.whatwg.org/#dom-document-createelementns
-  Element createElementNS(String namespaceUri, String tag) {
-    if (namespaceUri == '') namespaceUri = null;
-    return new Element._(tag, namespaceUri);
-  }
-
-  DocumentFragment createDocumentFragment() => new DocumentFragment();
-}
-
-class DocumentFragment extends Node
-    with _ParentNode, _NonElementParentNode {
-
-  DocumentFragment() : super._();
-  factory DocumentFragment.html(String html) => parseFragment(html);
-
-  int get nodeType => Node.DOCUMENT_FRAGMENT_NODE;
-
-  /// Returns a fragment of HTML or XML that represents the element and its
-  /// contents.
-  // TODO(jmesserly): this API is not specified in:
-  // <http://domparsing.spec.whatwg.org/> nor is it in dart:html, instead
-  // only Element has outerHtml. However it is quite useful. Should we move it
-  // to dom_parsing, where we keep other custom APIs?
-  String get outerHtml => _outerHtml;
-
-  String toString() => "#document-fragment";
-
-  DocumentFragment clone(bool deep) => _clone(new DocumentFragment(), deep);
-
-  void _addOuterHtml(StringBuffer str) => _addInnerHtml(str);
-
-  String get text => _getText(this);
-  set text(String value) => _setText(this, value);
-}
-
-class DocumentType extends Node {
-  final String name;
-  final String publicId;
-  final String systemId;
-
-  DocumentType(String name, this.publicId, this.systemId)
-      // Note: once Node.tagName is removed, don't pass "name" to super
-      : name = name, super._();
-
-  int get nodeType => Node.DOCUMENT_TYPE_NODE;
-
-  String toString() {
-    if (publicId != null || systemId != null) {
-      // TODO(jmesserly): the html5 serialization spec does not add these. But
-      // it seems useful, and the parser can handle it, so for now keeping it.
-      var pid = publicId != null ? publicId : '';
-      var sid = systemId != null ? systemId : '';
-      return '<!DOCTYPE $name "$pid" "$sid">';
-    } else {
-      return '<!DOCTYPE $name>';
-    }
-  }
-
-
-  void _addOuterHtml(StringBuffer str) {
-    str.write(toString());
-  }
-
-  DocumentType clone(bool deep) => new DocumentType(name, publicId, systemId);
-}
-
-class Text extends Node {
-  String data;
-
-  Text(this.data) : super._();
-
-  int get nodeType => Node.TEXT_NODE;
-
-  String toString() => '"$data"';
-
-  void _addOuterHtml(StringBuffer str) => writeTextNodeAsHtml(str, this);
-
-  Text clone(bool deep) => new Text(data);
-
-  String get text => data;
-  set text(String value) { data = value; }
-}
-
-// TODO(jmesserly): Elements should have a pointer back to their document
-class Element extends Node with _ParentNode, _ElementAndDocument {
-  final String namespaceUri;
-
-  /// The [local name](http://dom.spec.whatwg.org/#concept-element-local-name)
-  /// of this element.
-  final String localName;
-
-  Element._(this.localName, [this.namespaceUri]) : super._();
-
-  Element.tag(this.localName) : namespaceUri = Namespaces.html, super._();
-
-  static final _START_TAG_REGEXP = new RegExp('<(\\w+)');
-
-  static final _CUSTOM_PARENT_TAG_MAP = const {
-    'body': 'html',
-    'head': 'html',
-    'caption': 'table',
-    'td': 'tr',
-    'colgroup': 'table',
-    'col': 'colgroup',
-    'tr': 'tbody',
-    'tbody': 'table',
-    'tfoot': 'table',
-    'thead': 'table',
-    'track': 'audio',
-  };
-
-  // TODO(jmesserly): this is from dart:html _ElementFactoryProvider...
-  // TODO(jmesserly): have a look at fixing some things in dart:html, in
-  // particular: is the parent tag map complete? Is it faster without regexp?
-  // TODO(jmesserly): for our version we can do something smarter in the parser.
-  // All we really need is to set the correct parse state.
-  factory Element.html(String html) {
-
-    // TODO(jacobr): this method can be made more robust and performant.
-    // 1) Cache the dummy parent elements required to use innerHTML rather than
-    //    creating them every call.
-    // 2) Verify that the html does not contain leading or trailing text nodes.
-    // 3) Verify that the html does not contain both <head> and <body> tags.
-    // 4) Detatch the created element from its dummy parent.
-    String parentTag = 'div';
-    String tag;
-    final match = _START_TAG_REGEXP.firstMatch(html);
-    if (match != null) {
-      tag = match.group(1).toLowerCase();
-      if (_CUSTOM_PARENT_TAG_MAP.containsKey(tag)) {
-        parentTag = _CUSTOM_PARENT_TAG_MAP[tag];
-      }
-    }
-
-    var fragment = parseFragment(html, container: parentTag);
-    Element element;
-    if (fragment.children.length == 1) {
-      element = fragment.children[0];
-    } else if (parentTag == 'html' && fragment.children.length == 2) {
-      // You'll always get a head and a body when starting from html.
-      element = fragment.children[tag == 'head' ? 0 : 1];
-    } else {
-      throw new ArgumentError('HTML had ${fragment.children.length} '
-          'top level elements but 1 expected');
-    }
-    element.remove();
-    return element;
-  }
-
-  int get nodeType => Node.ELEMENT_NODE;
-
-  // TODO(jmesserly): we can make this faster
-  Element get previousElementSibling {
-    if (parentNode == null) return null;
-    var siblings = parentNode.nodes;
-    for (int i = siblings.indexOf(this) - 1; i >= 0; i--) {
-      var s = siblings[i];
-      if (s is Element) return s;
-    }
-    return null;
-  }
-
-  Element get nextElementSibling {
-    if (parentNode == null) return null;
-    var siblings = parentNode.nodes;
-    for (int i = siblings.indexOf(this) + 1; i < siblings.length; i++) {
-      var s = siblings[i];
-      if (s is Element) return s;
-    }
-    return null;
-  }
-
-  String toString() {
-    var prefix = Namespaces.getPrefix(namespaceUri);
-    return "<${prefix == null ? '' : '$prefix '}$localName>";
-  }
-
-  String get text => _getText(this);
-  set text(String value) => _setText(this, value);
-
-  /// Returns a fragment of HTML or XML that represents the element and its
-  /// contents.
-  String get outerHtml => _outerHtml;
-
-  /// Returns a fragment of HTML or XML that represents the element's contents.
-  /// Can be set, to replace the contents of the element with nodes parsed from
-  /// the given string.
-  String get innerHtml => _innerHtml;
-  // TODO(jmesserly): deprecate in favor of:
-  // <https://api.dartlang.org/apidocs/channels/stable/#dart-dom-html.Element@id_setInnerHtml>
-  set innerHtml(String value) {
-    nodes.clear();
-    // TODO(jmesserly): should be able to get the same effect by adding the
-    // fragment directly.
-    nodes.addAll(parseFragment(value, container: localName).nodes);
-  }
-
-  void _addOuterHtml(StringBuffer str) {
-    // http://www.whatwg.org/specs/web-apps/current-work/multipage/the-end.html#serializing-html-fragments
-    // Element is the most complicated one.
-    str.write('<${_getSerializationPrefix(namespaceUri)}$localName');
-
-    if (attributes.length > 0) {
-      attributes.forEach((key, v) {
-        // Note: AttributeName.toString handles serialization of attribute
-        // namespace, if needed.
-        str.write(' $key="${htmlSerializeEscape(v, attributeMode: true)}"');
-      });
-    }
-
-    str.write('>');
-
-    if (nodes.length > 0) {
-      if (localName == 'pre' || localName == 'textarea' ||
-          localName == 'listing') {
-        final first = nodes[0];
-        if (first is Text && first.data.startsWith('\n')) {
-          // These nodes will remove a leading \n at parse time, so if we still
-          // have one, it means we started with two. Add it back.
-          str.write('\n');
-        }
-      }
-
-      _addInnerHtml(str);
-    }
-
-    // void elements must not have an end tag
-    // http://dev.w3.org/html5/markup/syntax.html#void-elements
-    if (!isVoidElement(localName)) str.write('</$localName>');
-  }
-
-  static String _getSerializationPrefix(String uri) {
-    if (uri == null ||
-        uri == Namespaces.html ||
-        uri == Namespaces.mathml ||
-        uri == Namespaces.svg) {
-      return '';
-    }
-    var prefix = Namespaces.getPrefix(uri);
-    // TODO(jmesserly): the spec doesn't define "qualified name".
-    // I'm not sure if this is correct, but it should parse reasonably.
-    return prefix == null ? '' : '$prefix:';
-  }
-
-  Element clone(bool deep) {
-    var result = new Element._(localName, namespaceUri)
-        ..attributes = new LinkedHashMap.from(attributes);
-    return _clone(result, deep);
-  }
-
-  // http://dom.spec.whatwg.org/#dom-element-id
-  String get id {
-    var result = attributes['id'];
-    return result != null ? result : '';
-  }
-
-  set id(String value) {
-    attributes['id'] = '$value';
-  }
-
-  // http://dom.spec.whatwg.org/#dom-element-classname
-  String get className {
-    var result = attributes['class'];
-    return result != null ? result : '';
-  }
-
-  set className(String value) {
-    attributes['class'] = '$value';
-  }
-
-  /**
-   * The set of CSS classes applied to this element.
-   *
-   * This set makes it easy to add, remove or toggle the classes applied to
-   * this element.
-   *
-   *     element.classes.add('selected');
-   *     element.classes.toggle('isOnline');
-   *     element.classes.remove('selected');
-   */
-  CssClassSet get classes => new ElementCssClassSet(this);
-}
-
-class Comment extends Node {
-  String data;
-
-  Comment(this.data) : super._();
-
-  int get nodeType => Node.COMMENT_NODE;
-
-  String toString() => "<!-- $data -->";
-
-  void _addOuterHtml(StringBuffer str) {
-    str.write("<!--$data-->");
-  }
-
-  Comment clone(bool deep) => new Comment(data);
-
-  String get text => data;
-  set text(String value) {
-    this.data = value;
-  }
-}
-
-
-// TODO(jmesserly): fix this to extend one of the corelib classes if possible.
-// (The requirement to remove the node from the old node list makes it tricky.)
-// TODO(jmesserly): is there any way to share code with the _NodeListImpl?
-class NodeList extends ListProxy<Node> {
-  // Note: this is conceptually final, but because of circular reference
-  // between Node and NodeList we initialize it after construction.
-  Node _parent;
-
-  NodeList._();
-
-  Node get first => this[0];
-
-  Node _setParent(Node node) {
-    // Note: we need to remove the node from its previous parent node, if any,
-    // before updating its parent pointer to point at our parent.
-    node.remove();
-    node.parentNode = _parent;
-    return node;
-  }
-
-  void add(Node value) {
-    if (value is DocumentFragment) {
-      addAll(value.nodes);
-    } else {
-      super.add(_setParent(value));
-    }
-  }
-
-  void addLast(Node value) => add(value);
-
-  void addAll(Iterable<Node> collection) {
-    // Note: we need to be careful if collection is another NodeList.
-    // In particular:
-    //   1. we need to copy the items before updating their parent pointers,
-    //     _flattenDocFragments does a copy internally.
-    //   2. we should update parent pointers in reverse order. That way they
-    //      are removed from the original NodeList (if any) from the end, which
-    //      is faster.
-    var list = _flattenDocFragments(collection);
-    for (var node in list.reversed) _setParent(node);
-    super.addAll(list);
-  }
-
-  void insert(int index, Node value) {
-    if (value is DocumentFragment) {
-      insertAll(index, value.nodes);
-    } else {
-      super.insert(index, _setParent(value));
-    }
-  }
-
-  Node removeLast() => super.removeLast()..parentNode = null;
-
-  Node removeAt(int i) => super.removeAt(i)..parentNode = null;
-
-  void clear() {
-    for (var node in this) node.parentNode = null;
-    super.clear();
-  }
-
-  void operator []=(int index, Node value) {
-    if (value is DocumentFragment) {
-      removeAt(index);
-      insertAll(index, value.nodes);
-    } else {
-      this[index].parentNode = null;
-      super[index] = _setParent(value);
-    }
-  }
-
-  // TODO(jmesserly): These aren't implemented in DOM _NodeListImpl, see
-  // http://code.google.com/p/dart/issues/detail?id=5371
-  void setRange(int start, int rangeLength, List<Node> from,
-                [int startFrom = 0]) {
-    if (from is NodeList) {
-      // Note: this is presumed to make a copy
-      from = from.sublist(startFrom, startFrom + rangeLength);
-    }
-    // Note: see comment in [addAll]. We need to be careful about the order of
-    // operations if [from] is also a NodeList.
-    for (int i = rangeLength - 1; i >= 0; i--) {
-      this[start + i] = from[startFrom + i];
-    }
-  }
-
-  void replaceRange(int start, int end, Iterable<Node> newContents) {
-    removeRange(start, end);
-    insertAll(start, newContents);
-  }
-
-  void removeRange(int start, int rangeLength) {
-    for (int i = start; i < rangeLength; i++) this[i].parentNode = null;
-    super.removeRange(start, rangeLength);
-  }
-
-  void removeWhere(bool test(Element e)) {
-    for (var node in where(test)) {
-      node.parentNode = null;
-    }
-    super.removeWhere(test);
-  }
-
-  void retainWhere(bool test(Element e)) {
-    for (var node in where((n) => !test(n))) {
-      node.parentNode = null;
-    }
-    super.retainWhere(test);
-  }
-
-  void insertAll(int index, Iterable<Node> collection) {
-    // Note: we need to be careful how we copy nodes. See note in addAll.
-    var list = _flattenDocFragments(collection);
-    for (var node in list.reversed) _setParent(node);
-    super.insertAll(index, list);
-  }
-
-  _flattenDocFragments(Iterable<Node> collection) {
-    // Note: this function serves two purposes:
-    //  * it flattens document fragments
-    //  * it creates a copy of [collections] when `collection is NodeList`.
-    var result = [];
-    for (var node in collection) {
-      if (node is DocumentFragment) {
-        result.addAll(node.nodes);
-      } else {
-        result.add(node);
-      }
-    }
-    return result;
-  }
-}
-
-
-/// An indexable collection of a node's descendants in the document tree,
-/// filtered so that only elements are in the collection.
-// TODO(jmesserly): this was copied from dart:html
-// TODO(jmesserly): "implements List<Element>" is a workaround for analyzer bug.
-class FilteredElementList extends IterableBase<Element> with ListMixin<Element>
-    implements List<Element> {
-
-  final Node _node;
-  final List<Node> _childNodes;
-
-  /// Creates a collection of the elements that descend from a node.
-  ///
-  /// Example usage:
-  ///
-  ///     var filteredElements = new FilteredElementList(query("#container"));
-  ///     // filteredElements is [a, b, c].
-  FilteredElementList(Node node): _childNodes = node.nodes, _node = node;
-
-  // We can't memoize this, since it's possible that children will be messed
-  // with externally to this class.
-  //
-  // TODO(nweiz): we don't always need to create a new list. For example
-  // forEach, every, any, ... could directly work on the _childNodes.
-  List<Element> get _filtered =>
-    new List<Element>.from(_childNodes.where((n) => n is Element));
-
-  void forEach(void f(Element element)) {
-    _filtered.forEach(f);
-  }
-
-  void operator []=(int index, Element value) {
-    this[index].replaceWith(value);
-  }
-
-  void set length(int newLength) {
-    final len = this.length;
-    if (newLength >= len) {
-      return;
-    } else if (newLength < 0) {
-      throw new ArgumentError("Invalid list length");
-    }
-
-    removeRange(newLength, len);
-  }
-
-  String join([String separator = ""]) => _filtered.join(separator);
-
-  void add(Element value) {
-    _childNodes.add(value);
-  }
-
-  void addAll(Iterable<Element> iterable) {
-    for (Element element in iterable) {
-      add(element);
-    }
-  }
-
-  bool contains(Element element) {
-    return element is Element && _childNodes.contains(element);
-  }
-
-  Iterable<Element> get reversed => _filtered.reversed;
-
-  void sort([int compare(Element a, Element b)]) {
-    throw new UnsupportedError('TODO(jacobr): should we impl?');
-  }
-
-  void setRange(int start, int end, Iterable<Element> iterable,
-                [int skipCount = 0]) {
-    throw new UnimplementedError();
-  }
-
-  void fillRange(int start, int end, [Element fillValue]) {
-    throw new UnimplementedError();
-  }
-
-  void replaceRange(int start, int end, Iterable<Element> iterable) {
-    throw new UnimplementedError();
-  }
-
-  void removeRange(int start, int end) {
-    _filtered.sublist(start, end).forEach((el) => el.remove());
-  }
-
-  void clear() {
-    // Currently, ElementList#clear clears even non-element nodes, so we follow
-    // that behavior.
-    _childNodes.clear();
-  }
-
-  Element removeLast() {
-    final result = this.last;
-    if (result != null) {
-      result.remove();
-    }
-    return result;
-  }
-
-  Iterable map(f(Element element)) => _filtered.map(f);
-  Iterable<Element> where(bool f(Element element)) => _filtered.where(f);
-  Iterable expand(Iterable f(Element element)) => _filtered.expand(f);
-
-  void insert(int index, Element value) {
-    _childNodes.insert(index, value);
-  }
-
-  void insertAll(int index, Iterable<Element> iterable) {
-    _childNodes.insertAll(index, iterable);
-  }
-
-  Element removeAt(int index) {
-    final result = this[index];
-    result.remove();
-    return result;
-  }
-
-  bool remove(Object element) {
-    if (element is! Element) return false;
-    for (int i = 0; i < length; i++) {
-      Element indexElement = this[i];
-      if (identical(indexElement, element)) {
-        indexElement.remove();
-        return true;
-      }
-    }
-    return false;
-  }
-
-  Element reduce(Element combine(Element value, Element element)) {
-    return _filtered.reduce(combine);
-  }
-
-  dynamic fold(dynamic initialValue,
-      dynamic combine(dynamic previousValue, Element element)) {
-    return _filtered.fold(initialValue, combine);
-  }
-
-  bool every(bool f(Element element)) => _filtered.every(f);
-  bool any(bool f(Element element)) => _filtered.any(f);
-  List<Element> toList({ bool growable: true }) =>
-      new List<Element>.from(this, growable: growable);
-  Set<Element> toSet() => new Set<Element>.from(this);
-  Element firstWhere(bool test(Element value), {Element orElse()}) {
-    return _filtered.firstWhere(test, orElse: orElse);
-  }
-
-  Element lastWhere(bool test(Element value), {Element orElse()}) {
-    return _filtered.lastWhere(test, orElse: orElse);
-  }
-
-  Element singleWhere(bool test(Element value)) {
-    return _filtered.singleWhere(test);
-  }
-
-  Element elementAt(int index) {
-    return this[index];
-  }
-
-  bool get isEmpty => _filtered.isEmpty;
-  int get length => _filtered.length;
-  Element operator [](int index) => _filtered[index];
-  Iterator<Element> get iterator => _filtered.iterator;
-  List<Element> sublist(int start, [int end]) =>
-    _filtered.sublist(start, end);
-  Iterable<Element> getRange(int start, int end) =>
-    _filtered.getRange(start, end);
-  int indexOf(Element element, [int start = 0]) =>
-    _filtered.indexOf(element, start);
-
-  int lastIndexOf(Element element, [int start = null]) {
-    if (start == null) start = length - 1;
-    return _filtered.lastIndexOf(element, start);
-  }
-
-  Element get first => _filtered.first;
-
-  Element get last => _filtered.last;
-
-  Element get single => _filtered.single;
-}
-
-// http://dom.spec.whatwg.org/#dom-node-textcontent
-// For Element and DocumentFragment
-String _getText(Node node) =>
-    (new _ConcatTextVisitor()..visit(node)).toString();
-
-void _setText(Node node, String value) {
-  node.nodes.clear();
-  node.append(new Text(value));
-}
-
-class _ConcatTextVisitor extends TreeVisitor {
-  final _str = new StringBuffer();
-
-  String toString() => _str.toString();
-
-  visitText(Text node) {
-    _str.write(node.data);
-  }
-}