- Fix use of String operator + in language and corelib tests.

tests/language/src/InterfaceFactoryMultiTest.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.
 //
 
 // Test that a factory provider can provide for more than one interface.
 
 interface A default F {
   A(var secret);
 
   GetSecret();
 }
 
 class AImpl implements A {
   String _secret;
 
-  AImpl(String one, String two) : _secret = one + two;
+  AImpl(String one, String two) : _secret = one.concat(two);

[kasperl, 2012/03/12 06:55:42]

_secret = "${one}${two}"

[Ivan Posva, 2012/04/11 14:26:00]

Done.

 
   String GetSecret() { return _secret; }
 }
 
 interface B default F {
   B(var secret);
 
   GetSecret();
 }
 
 class BImpl implements B {
   String _secret;
 
-  BImpl(String one, String two) : _secret = two + one;
+  BImpl(String one, String two) : _secret = two.concat(one);

[kasperl, 2012/03/12 06:55:42]

_secret = "${two}${one}"

[Ivan Posva, 2012/04/11 14:26:00]

Done.

 
   String GetSecret() { return _secret; }
 }
 
 
 // One factory provider for two interfaces.
 class F {
   factory A(var secret) {
     return new AImpl(secret, 'A');
   }
 
   factory B(var secret) {
     return new BImpl(secret, 'B');
   }
 }
 
 main() {
   Expect.equals('1A', new A('1').GetSecret());
   Expect.equals('B2', new B('2').GetSecret());
 }