Roll Observatory packages and add a roll script

packages/collection/lib/src/queue_list.dart

 // Copyright (c) 2014, 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.
 
 import 'dart:collection';
 
 /**
  * A class that efficiently implements both [Queue] and [List].
  */
 // TODO(nweiz): Currently this code is copied almost verbatim from
@@ skipping 211 matching lines @@
     // Add 1.5x extra room to ensure that there's room for more elements after
     // expansion.
     newElementCount += newElementCount >> 1;
     int newCapacity = _nextPowerOf2(newElementCount);
     List<E> newTable = new List<E>(newCapacity);
     _tail = _writeToList(newTable);
     _table = newTable;
     _head = 0;
   }
 }