Clean up VM class DartFunction.

runtime/vm/object.cc

Index: runtime/vm/object.cc
===================================================================
--- runtime/vm/object.cc	(revision 26047)
+++ runtime/vm/object.cc	(working copy)
@@ -1080,9 +1080,9 @@
   type = object_store->object_type();
   cls.set_super_type(type);
 
-  // Note: The abstract class Function is represented by VM class
-  // DartFunction, not VM class Function.
-  cls = Class::New<DartFunction>();
+  // Abstract class that represents the Dart class Function.
+  cls = Class::New<Instance>(kIllegalCid);
+  cls.set_is_prefinalized();
   RegisterClass(cls, Symbols::Function(), core_lib);
   pending_classes.Add(cls, Heap::kOld);
   type = Type::NewNonParameterizedType(cls);
@@ -1255,7 +1255,6 @@
   // Some classes are not stored in the object store. Yet we still need to
   // create their Class object so that they get put into the class_table
   // (as a side effect of Class::New()).
-  cls = Class::New<DartFunction>();
   cls = Class::New<Number>();
 
   cls = Class::New<WeakProperty>();
@@ -14191,17 +14190,6 @@
 }
 
 
-const char* DartFunction::ToCString() const {
-  return "Function type class";
-}
-
-
-void DartFunction::PrintToJSONStream(JSONStream* stream, bool ref) const {
-  stream->OpenObject();
-  stream->CloseObject();
-}
-
-
 intptr_t Stacktrace::Length() const {
   const Array& code_array = Array::Handle(raw_ptr()->code_array_);
   return code_array.Length();