Don't hide interceptors in mirrors.

sdk/lib/_internal/compiler/implementation/ssa/ssa_tracer.dart

 // Copyright (c) 2013, 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 ssa.tracer;
 
 import 'dart:async' show EventSink;
 
 import 'ssa.dart';
 import '../js_backend/js_backend.dart';
@@ skipping 285 matching lines @@
 
   String visitInvokeClosure(HInvokeClosure node)
       => visitInvokeDynamic(node, "closure");
 
   String visitInvokeDynamic(HInvokeDynamic invoke, String kind) {
     String receiver = temporaryId(invoke.receiver);
     String name = invoke.selector.name;
     String target = "($kind) $receiver.$name";
     int offset = HInvoke.ARGUMENTS_OFFSET;
     List arguments = invoke.inputs.sublist(offset);
-    return visitGenericInvoke("Invoke", target, arguments);
+    return visitGenericInvoke("Invoke", target, arguments) +
+        "(${invoke.selector.mask})";
   }
 
   String visitInvokeDynamicMethod(HInvokeDynamicMethod node)
       => visitInvokeDynamic(node, "method");
   String visitInvokeDynamicGetter(HInvokeDynamicGetter node)
       => visitInvokeDynamic(node, "get");
   String visitInvokeDynamicSetter(HInvokeDynamicSetter node)
       => visitInvokeDynamic(node, "set");
 
   String visitInvokeStatic(HInvokeStatic invoke) {
@@ skipping 194 matching lines @@
   }
 
   String visitInterfaceType(HInterfaceType node) {
     return "InterfaceType: ${node.dartType}";
   }
 
   String visitDynamicType(HDynamicType node) {
     return "DynamicType";
   }
 }