Rename String.concat to operator+.

runtime/lib/invocation_mirror_patch.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.
 
 class _InvocationMirror implements InvocationMirror {
   // Constants describing the invocation type.
   // _FIELD cannot be generated by regular invocation mirrors.
   static const int _METHOD = 0;
   static const int _GETTER = 1;
   static const int _SETTER = 2;
@@ skipping 22 matching lines @@
   int _type;
   List _positionalArguments;
   Map<String, dynamic> _namedArguments;
 
   void _setMemberNameAndType() {
     if (_functionName.startsWith("get:")) {
       _type = _GETTER;
       _memberName = _functionName.substring(4);
     } else if (_functionName.startsWith("set:")) {
       _type = _SETTER;
-      _memberName = _functionName.substring(4).concat("=");
+      _memberName = _functionName.substring(4) + "=";
     } else {
       _type = _METHOD;
       _memberName = _functionName;
     }
   }
 
   String get memberName {
     if (_memberName == null) {
       _setMemberNameAndType();
     }
@@ skipping 66 matching lines @@
                  String functionName,
                  List argumentsDescriptor,
                  List arguments)
       native "InvocationMirror_invoke";
 
   invokeOn(Object receiver) {
     return _invoke(receiver, _functionName, _argumentsDescriptor, _arguments);
   }
 }