Remove support for obsolete syntax of factory methods and default classes.

tests/language/src/NonParameterizedFactory2Test.dart

 // Copyright (c) 2011, 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.
 
-interface Interface<T> default Factory {

[zundel, 2012/01/24 22:52:40]

I'm not seeing a change to the spec since I last worked on the default class
specification, did you confirm with Gilad?

At the time,  this syntax was OK with the new 'default' syntax - in fact, this
test is to show that you can use the non-parameterized type with a parameterized
default class if you like.  



https://docs.google.com/a/google.com/document/pub?id=1RqcfL64kw5SJkyut6eN34d7...

  "If the default factory clause of I includes a list of type parameters tps,
then tps must be identical to the type parameters given in the type declaration
of F, or a compile-time error occurs."  

+interface Interface<T> default Factory<T> {
   Interface();
   Interface.withArg(T value);
 }
 
 class Factory<T> {
   factory Interface() {
     return null;
   }
 
   factory Interface.withArg(value) {
     return null;
   }
 }
 
 main() {
   new Interface<int>();
   new Interface<int>.withArg(4);
 }