Fix bugs in GrowableList.remove*.

sdk/lib/core/collection.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.
 
 part of dart.core;
 
 /**
  * A collection of individual elements.
  *
  * A [Collection] contains some elements in a structure optimized
@@ skipping 66 matching lines @@
   }
 
   /**
    * Removes all elements of this collection that fail to satisfy [test].
    *
    * An elements [:e:] satisfies [test] if [:test(e):] is true.
    */
   void retainMatching(bool test(E element)) {
     IterableMixinWorkaround.retainMatching(this, test);
   }
+
+  /**
+   * Removes all elements of this collection.
+   */
+  void clear() {
+    IterableMixinWorkaround.removeMatching((E e) => true);
+  }
 }