Add "contains" method to Collection.

runtime/lib/array.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.
 
 
 // TODO(srdjan): Use shared array implementation.
 class _ObjectArray<E> implements List<E> {
 
   factory _ObjectArray(int length) native "ObjectArray_allocate";
 
@@ skipping 41 matching lines @@
 
   List<E> getRange(int start, int length) {
     if (length == 0) return [];
     Arrays.rangeCheck(this, start, length);
     List list = new _GrowableObjectArray<E>.withCapacity(length);
     list.length = length;
     Arrays.copy(this, start, list, 0, length);
     return list;
   }
 
-  /**
-   * Collection interface.
-   */
+  // Collection interface.
+
+  bool contains(E element) => Collections.contains(this, element);
 
   void forEach(f(E element)) {
     Collections.forEach(this, f);
   }
 
   Collection map(f(E element)) {
     return Collections.map(
         this, new _GrowableObjectArray.withCapacity(length), f);
   }
 
@@ skipping 119 matching lines @@
 
   List<E> getRange(int start, int length) {
     if (length == 0) return [];
     Arrays.rangeCheck(this, start, length);
     List list = new List<E>();
     list.length = length;
     Arrays.copy(this, start, list, 0, length);
     return list;
   }
 
-  /**
-   * Collection interface.
-   */
+  // Collection interface.
+
+  bool contains(E element) => Collections.contains(this, element);
 
   void forEach(f(E element)) {
     Collections.forEach(this, f);
   }
 
   Collection map(f(E element)) {
     return Collections.map(
         this, new _GrowableObjectArray.withCapacity(length), f);
   }
 
@@ skipping 89 matching lines @@
     if (!hasNext()) {
       throw const NoMoreElementsException();
     }
     return _array[_pos++];
   }
 
   final List<E> _array;
   final int _length;  // Cache array length for faster access.
   int _pos;
 }