Roll Observatory packages and add a roll script

packages/quiver/lib/src/collection/delegates/queue.dart

 // Copyright 2013 Google Inc. All Rights Reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 32 matching lines @@
   bool remove(Object object) => delegate.remove(object);
 
   E removeFirst() => delegate.removeFirst();
 
   E removeLast() => delegate.removeLast();
 
   void removeWhere(bool test(E element)) => delegate.removeWhere(test);
 
   void retainWhere(bool test(E element)) => delegate.retainWhere(test);
 }