Make Null a public class of dart:core.

runtime/vm/object.cc

Index: runtime/vm/object.cc
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index 34fccc0da35f0e2f171071406b9559af35f44eef..420adcbe459c13b4881e0ff027b050864b7b3468 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -417,7 +417,6 @@ void Object::InitOnce() {
 
   // Allocate and initialize the null class.
   cls = Class::New<Instance>(kNullCid);
-  cls.set_is_prefinalized();
   isolate->object_store()->set_null_class(cls);

[regis, 2013/08/15 17:27:26]

Shouldn't this be done in Object::InitFromSnapshot, exactly like for
object_class?

[rmacnak, 2013/08/15 17:56:04]

object_class is also created in both Init(Isolate*) and InitFromSnapshot.

 
   // Allocate and initialize the free list element class.
@@ -854,11 +853,9 @@ RawError* Object::Init(Isolate* isolate) {
   RegisterClass(cls, Symbols::Bool(), core_lib);
   pending_classes.Add(cls, Heap::kOld);
 
-  // TODO(12364): The class 'Null' is not registered in the class dictionary
-  // because it is not exported by dart:core.
   cls = Class::New<Instance>(kNullCid);
-  object_store->set_null_class(cls);
   cls.set_is_prefinalized();
+  object_store->set_null_class(cls);
   RegisterClass(cls, Symbols::Null(), core_lib);
   pending_classes.Add(cls, Heap::kOld);

[regis, 2013/08/15 17:27:26]

Shouldn't this paragraph be moved to after the comment "Allocate and initialize
the pre-allocated classes in the core library." below, since Null is now found
in the core lib? Not required, though.

[rmacnak, 2013/08/15 17:56:04]

Moved null and bool down.

 
@@ -10468,13 +10465,13 @@ RawString* AbstractType::ClassName() const {
 
 bool AbstractType::IsNullType() const {
   return HasResolvedTypeClass() &&
-      (type_class() == Type::Handle(Type::NullType()).type_class());
+      (type_class() == Isolate::Current()->object_store()->null_class());
 }
 
 
 bool AbstractType::IsBoolType() const {
   return HasResolvedTypeClass() &&
-      (type_class() == Type::Handle(Type::BoolType()).type_class());
+      (type_class() == Isolate::Current()->object_store()->bool_class());
 }