Hide internal classes from Memory Profile

runtime/observatory/lib/src/models/objects/allocation_profile.dart

 // Copyright (c) 2016, 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
 
 part of models;
 
 abstract class AllocationProfile {
   DateTime get lastServiceGC;
   DateTime get lastAccumulatorReset;
   HeapSpace get newSpace;
   HeapSpace get oldSpace;
   Iterable<ClassHeapStats> get members;
 }
 
 abstract class ClassHeapStats {
+  /// [Optional] at least one between clazz and displayName should be non null
   ClassRef get clazz;
+
+  /// [Optional] at least one between clazz and displayName should be non null
+  String get displayName;
   Allocations get newSpace;
   Allocations get oldSpace;
   int get promotedInstances;
   int get promotedBytes;
 }
 
 abstract class Allocations {
   AllocationCount get accumulated;
   AllocationCount get current;
 }
 
 abstract class AllocationCount {
   int get instances;
   int get bytes;
 }