Get rid of a lot of () for getters.

samples/maps/js.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.
 
 // The js.dart library provides simple synchronous JS invocation from
 // Dart in a browser setting (Dartium or via dart2js).
 //
 // Methods
 //   (1) js.invoke invokes a JS method (specified by string) on a
 //       list of serializable parameters in the DOM window's JS context and
@@ skipping 325 matching lines @@
   
   operator [](key) => _fail();
   operator []=(key, value) => _fail();
   clear() => _fail();
   containsKey(key) => _fail();
   containsValue(value) => _fail();
   forEach(f) => _fail();
   getKeys() => _fail();
   getValues() => _fail();
   isEmpty() => _fail();
-  get length() => _fail();
+  get length => _fail();
   putIfAbsent(key, ifAbsent) => _fail();
   remove(key) => _fail();
 }
 
 /**
  * An abstract base type for Dart types that automatically serialize
  * to JavaScript via JSON.
  */
 class Serializable extends _SerializableMap {
 
@@ skipping 13 matching lines @@
     result[_DESERIALIZER] = jsDeserializer;
     result[_ARGUMENTS] = arguments;
     return result;
   }
 
   /**
    * Create a legal JSON Map from this object.
    */
   abstract Map<String, Object> serialize();
 }