Do not eagerly add guarded leaf classes with CHA; do not add them for private names.

runtime/vm/object.cc

 // 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.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 3773 matching lines @@
                               other_type_arguments,
                               bound_error);
 }
 
 
 bool Class::IsTopLevel() const {
   return Name() == Symbols::TopLevel().raw();
 }
 
 
+bool Class::IsPrivate() const {
+  return Library::IsPrivate(String::Handle(Name()));
+}
+
+
 RawFunction* Class::LookupDynamicFunction(const String& name) const {
   return LookupFunction(name, kInstance);
 }
 
 
 RawFunction* Class::LookupDynamicFunctionAllowPrivate(
     const String& name) const {
   return LookupFunctionAllowPrivate(name, kInstance);
 }
 
@@ skipping 16989 matching lines @@
   return tag_label.ToCString();
 }
 
 
 void UserTag::PrintJSONImpl(JSONStream* stream, bool ref) const {
   Instance::PrintJSONImpl(stream, ref);
 }
 
 
 }  // namespace dart