Do not hide membership of implementation classes in dart:core.

runtime/lib/mirrors.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 "lib/invocation_mirror.h"
 #include "vm/bootstrap_natives.h"
 #include "vm/class_finalizer.h"
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
 #include "vm/exceptions.h"
@@ skipping 1099 matching lines @@
 
   Object& entry = Object::Handle();
   DictionaryIterator entries(library);
 
   AbstractType& type = AbstractType::Handle();
 
   while (entries.HasNext()) {
     entry = entries.GetNext();
     if (entry.IsClass()) {
       const Class& klass = Class::Cast(entry);
-      // We filter out implementation classes like Smi, Mint, Bignum,
-      // OneByteString; function signature classes; and dynamic.
+      // We filter out function signature classes and dynamic.
+      // TODO(12478): Should not need to filter out dynamic.
       if (!klass.IsCanonicalSignatureClass() &&
-          !klass.IsDynamicClass() &&
-          !RawObject::IsImplementationClassId(klass.id())) {

[rmacnak, 2013/10/14 21:18:03]

We originally filtered these out because we were using UserVisibleName as the
key for classes. In the version of mirrors that used the embedding API,
superclasses and interfaces were looked up by name rather than by reference, and
we got into problems where, say, OneByteString would be added to the core
library's members after String and replace it in the map and produce incorrect
results. Now that we are properly looking for superclasses, interfaces, etc by
reference and we aren't using UserVisibleName, we can correctly admit to the
membership of these classes.

+          !klass.IsDynamicClass()) {
         type = klass.RareType();
         member_mirror = CreateClassMirror(klass,
                                           type,
                                           Bool::True(),  // is_declaration
                                           owner_mirror);
         member_mirrors.Add(member_mirror);
       }
     } else if (entry.IsField()) {
       const Field& field = Field::Cast(entry);
       member_mirror = CreateVariableMirror(field, owner_mirror);
@@ skipping 720 matching lines @@
 }
 
 
 DEFINE_NATIVE_ENTRY(VariableMirror_type, 1) {
   GET_NON_NULL_NATIVE_ARGUMENT(MirrorReference, ref, arguments->NativeArgAt(0));
   const Field& field = Field::Handle(ref.GetFieldReferent());
   return field.type();
 }
 
 }  // namespace dart