Remove stale files from lib/html/src.

lib/html/src/CssClassSet.dart

-// Copyright (c) 2011, 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.
-
-// TODO - figure out whether classList exists, and if so use that
-// rather than the className property that is being used here.
-
-class _CssClassSet implements Set<String> {
-
-  final _element;
-
-  _CssClassSet(this._element);
-
-  String toString() {
-    return _formatSet(_read());
-  }
-
-  // interface Iterable - BEGIN
-  Iterator<String> iterator() {
-    return _read().iterator();
-  }
-  // interface Iterable - END
-
-  // interface Collection - BEGIN
-  void forEach(void f(String element)) {
-    _read().forEach(f);
-  }
-
-  Collection map(f(String element)) {
-    return _read().map(f);
-  }
-
-  Collection<String> filter(bool f(String element)) {
-    return _read().filter(f);
-  }
-
-  bool every(bool f(String element)) {
-    return _read().every(f);
-  }
-
-  bool some(bool f(String element)) {
-    return _read().some(f);
-  }
-
-  bool isEmpty() {
-    return _read().isEmpty();
-  }
-
-  int get length() {
-    return _read().length;
-  }
-  // interface Collection - END
-
-  // interface Set - BEGIN
-  bool contains(String value) {
-    return _read().contains(value);
-  }
-
-  void add(String value) {
-    // TODO - figure out if we need to do any validation here
-    // or if the browser natively does enough
-    _modify((s) => s.add(value));
-  }
-
-  bool remove(String value) {
-    Set<String> s = _read();
-    bool result = s.remove(value);
-    _write(s);
-    return result;
-  }
-
-  void addAll(Collection<String> collection) {
-    // TODO - see comment above about validation
-    _modify((s) => s.addAll(collection));
-  }
-
-  void removeAll(Collection<String> collection) {
-    _modify((s) => s.removeAll(collection));
-  }
-
-  bool isSubsetOf(Collection<String> collection) {
-    return _read().isSubsetOf(collection);
-  }
-
-  bool containsAll(Collection<String> collection) {
-    return _read().containsAll(collection);
-  }
-
-  Set<String> intersection(Collection<String> other) {
-    return _read().intersection(other);
-  }
-
-  void clear() {
-    _modify((s) => s.clear());
-  }
-  // interface Set - END
-
-  /**
-   * Helper method used to modify the set of css classes on this element.
-   *
-   *   f - callback with:
-   *      s - a Set of all the css class name currently on this element.
-   *
-   *   After f returns, the modified set is written to the
-   *       className property of this element.
-   */
-  void _modify( f(Set<String> s)) {
-    Set<String> s = _read();
-    f(s);
-    _write(s);
-  }
-
-  /**
-   * Read the class names from the HTMLElement class property,
-   * and put them into a set (duplicates are discarded).
-   */
-  Set<String> _read() {
-    // TODO(mattsh) simplify this once split can take regex.
-    Set<String> s = new Set<String>();
-    for (String name in _className().split(' ')) {
-      String trimmed = name.trim();
-      if (!trimmed.isEmpty()) {
-        s.add(trimmed);
-      }
-    }
-    return s;
-  }
-
-  /**
-   * Read the class names as a space-separated string. This is meant to be
-   * overridden by subclasses.
-   */
-  String _className() => _element.className;
-
-  /**
-   * Join all the elements of a set into one string and write
-   * back to the element.
-   */
-  void _write(Set s) {
-    _element.className = _formatSet(s);
-  }
-
-  String _formatSet(Set<String> s) {
-    // TODO(mattsh) should be able to pass Set to String.joins http:/b/5398605
-    List list = new List.from(s);
-    return Strings.join(list, ' ');
-  }
-
-}
-