Convert NoMoreElementsException and EmptyQueueException to StateError.

lib/coreimpl/queue.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.
 
 
 /**
  * An entry in a doubly linked list. It contains a pointer to the next
  * entry, the previous entry, and the boxed element.
  */
 class DoubleLinkedQueueEntry<E> {
@@ skipping 56 matching lines @@
  * is the only entry when the list is constructed. Initially, a
  * sentinel has its next and previous entry point to itself. A
  * sentinel does not box any user element.
  */
 class _DoubleLinkedQueueEntrySentinel<E> extends DoubleLinkedQueueEntry<E> {
   _DoubleLinkedQueueEntrySentinel() : super(null) {
     _link(this, this);
   }
 
   E remove() {
-    throw const EmptyQueueException();
+    throw new StateError("Empty queue");
   }
 
   DoubleLinkedQueueEntry<E> _asNonSentinelEntry() {
     return null;
   }
 
   void set element(E e) {
     // This setter is unreachable.
     assert(false);
   }
 
   E get element {
-    throw const EmptyQueueException();
+    throw new StateError("Empty queue");
   }
 }
 
 /**
  * Implementation of a double linked list that box list elements into
  * DoubleLinkedQueueEntry objects.
  */
 class DoubleLinkedQueue<E> implements Queue<E> {
   _DoubleLinkedQueueEntrySentinel<E> _sentinel;
 
@@ skipping 147 matching lines @@
   _DoubleLinkedQueueIterator(_DoubleLinkedQueueEntrySentinel this._sentinel) {
     _currentEntry = _sentinel;
   }
 
   bool get hasNext {
     return _currentEntry._next !== _sentinel;
   }
 
   E next() {
     if (!hasNext) {
-      throw const NoMoreElementsException();
+      throw new StateError("No more elements");
     }
     _currentEntry = _currentEntry._next;
     return _currentEntry.element;
   }
 }