Get rid of a lot of () for getters.

lib/coreimpl/hash_map_set.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.
 
 // Hash map implementation with open addressing and quadratic probing.
 class HashMapImplementation<K extends Hashable, V> implements HashMap<K, V> {
 
   // The [_keys] list contains the keys inserted in the map.
   // The [_keys] list must be a raw list because it
   // will contain both elements of type K, and the [_DELETED_KEY] of type
@@ skipping 203 matching lines @@
       _numberOfDeleted++;
       return value;
     }
     return null;
   }
 
   bool isEmpty() {
     return _numberOfEntries == 0;
   }
 
-  int get length() {
+  int get length {
     return _numberOfEntries;
   }
 
   void forEach(void f(K key, V value)) {
     int length = _keys.length;
     for (int i = 0; i < length; i++) {
       var key = _keys[i];
       if ((key !== null) && (key !== _DELETED_KEY)) {
         f(key, _values[i]);
       }
@@ skipping 135 matching lines @@
 
   bool some(bool f(E element)) {
     Collection<E> keys = _backingMap.getKeys();
     return keys.some(f);
   }
 
   bool isEmpty() {
     return _backingMap.isEmpty();
   }
 
-  int get length() {
+  int get length {
     return _backingMap.length;
   }
 
   Iterator<E> iterator() {
     return new HashSetIterator<E>(this);
   }
 
   String toString() {
     return Collections.collectionToString(this);
   }
@@ skipping 54 matching lines @@
 
 /**
  * A singleton sentinel used to represent when a key is deleted from the map.
  * We can't use [: const Object() :] as a sentinel because it would end up
  * canonicalized and then we cannot distinguish the deleted key from the
  * canonicalized [: Object() :].
  */
 class _DeletedKeySentinel {
   const _DeletedKeySentinel();
 }