Add support for superSend to the new IR and dart backend.

sdk/lib/_internal/compiler/implementation/dart_backend/tree_tracer.dart

 // Copyright (c) 2014, 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.
 
 library dart_backend.tracer;
 
 import 'dart:async' show EventSink;
 import '../tracer.dart';
 import 'dart_tree.dart';
 
@@ skipping 273 matching lines @@
     return "$head($args)";
   }
 
   String visitInvokeMethod(InvokeMethod node) {
     String receiver = node.receiver.accept(this);
     String name = node.selector.name;
     String args = formatArguments(node);
     return "$receiver.$name($args)";
   }
 
+  String visitInvokeSuperMethod(InvokeSuperMethod node) {
+    String name = node.selector.name;
+    String args = formatArguments(node);
+    return "super.$name($args)";
+  }
+
   String visitInvokeConstructor(InvokeConstructor node) {
     String callName;
     if (node.target.name.isEmpty) {
       callName = '${node.type}';
     } else {
       callName = '${node.type}.${node.target.name}';
     }
     String args = formatArguments(node);
     String keyword = node.constant != null ? 'const' : 'new';
     return "$keyword $callName($args)";
@@ skipping 88 matching lines @@
       String prefix = v.element == null ? 'v' : '${v.element.name}_';
       while (name == null || _usedNames.contains(name)) {
         name = "$prefix${_counter++}";
       }
       _names[v] = name;
       _usedNames.add(name);
     }
     return name;
   }
 }