Make Set.containsAll accept Iterable. Deprecate Set.isSubsetOf.

sdk/lib/collection/collections.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.
 
 part of dart.collection;
 
 /**
  * This class provides default implementations for Iterables (including Lists).
  *
  * Once Dart receives Mixins it will be replaced with mixin classes.
@@ skipping 364 matching lines @@
       throw new RangeError.value(start + length);
     }
 
     Arrays.copy(from, startFrom, list, start, length);
   }
 
   static Map<int, dynamic> asMapList(List l) {
     return new ListMapView(l);
   }
 
-  static bool isSubsetOfSet(Set set, Set other) {
-    if (set.length > other.length) return false;
-    for (var element in set) {
-      if (!other.contains(element)) return false;
+  static bool setContainsAll(Set set, Iterable other) {
+    for (var element in other) {
+      if (!set.contains(element)) return false;
     }
     return true;
   }
 
-
   static Set setIntersection(Set set, Set other, Set result) {
     Set smaller;
     Set larger;
     if (set.length < other.length) {
       smaller = set;
       larger = other;
     } else {
       smaller = other;
       larger = set;
     }
@@ skipping 32 matching lines @@
  * The source of the elements may be a [List] or any [Iterable] with
  * efficient [Iterable.length] and [Iterable.elementAt].
  */
 class UnmodifiableListView<E> extends UnmodifiableListBase<E> {
   Iterable<E> _source;
   /** Create an unmodifiable list backed by [source]. */
   UnmodifiableListView(Iterable<E> source) : _source = source;
   int get length => _source.length;
   E operator[](int index) => _source.elementAt(index);
 }