Use patching for Expando so the implementation-specific files are not needed in the SDK.

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/bigint_operations.h"
@@ skipping 611 matching lines @@
   RegisterClass(cls, name, core_impl_lib);
   pending_classes.Add(cls, Heap::kOld);
   // Super type set below, after Object is allocated.
 
   cls = Class::New<JSRegExp>();
   object_store->set_jsregexp_class(cls);
   name = Symbols::JSSyntaxRegExp();
   RegisterClass(cls, name, core_impl_lib);
   pending_classes.Add(cls, Heap::kOld);
 
+  cls = Class::New<WeakProperty>();
+  object_store->set_weak_property_class(cls);
+  name = Symbols::_WeakProperty();
+  RegisterPrivateClass(cls, name, core_impl_lib);
+  pending_classes.Add(cls, Heap::kOld);

[Mads Ager (google), 2012/08/24 11:15:23]

Carl, this reflects the move of the class from core to coreimpl. I added the
addition to pending_classes just to keep it consistent with the above. Is that
the right thing to do or should I leave out the addition to pending_classes?

[cshapiro, 2012/08/25 03:18:29]

I believe you have done the right thing.  

When something goes wrong in this function, you tend to find out pretty quickly.
 If you have run all of the unit tests and they have passed, I think you can be
confident that this change is okay.

+
   // Initialize the base interfaces used by the core VM classes.
   const Script& script = Script::Handle(Bootstrap::LoadCoreScript(false));
 
   // Allocate and initialize the Object class and type.  The Object
   // class and ByteArray subclasses are the only pre-allocated,
   // non-interface classes in the core library.
   cls = Class::New<Instance>(kInstanceCid);
   object_store->set_object_class(cls);
   name = Symbols::Object();
   cls.set_name(name);
@@ skipping 97 matching lines @@
   cls = Class::New<ExternalFloat32Array>();
   object_store->set_external_float32_array_class(cls);
   name = Symbols::_ExternalFloat32Array();
   RegisterPrivateClass(cls, name, core_lib);
 
   cls = Class::New<ExternalFloat64Array>();
   object_store->set_external_float64_array_class(cls);
   name = Symbols::_ExternalFloat64Array();
   RegisterPrivateClass(cls, name, core_lib);
 
-  cls = Class::New<WeakProperty>();
-  object_store->set_weak_property_class(cls);
-  name = Symbols::_WeakProperty();
-  RegisterPrivateClass(cls, name, core_lib);
-
   // Set the super type of class Stacktrace to Object type so that the
   // 'toString' method is implemented.
   cls = object_store->stacktrace_class();
   cls.set_super_type(type);
 
   // Note: The abstract class Function is represented by VM class
   // DartFunction, not VM class Function.
   name = Symbols::Function();
   cls = Class::New<DartFunction>();
   RegisterClass(cls, name, core_lib);
@@ skipping 10417 matching lines @@
   }
   return result.raw();
 }
 
 
 const char* WeakProperty::ToCString() const {
   return "_WeakProperty";
 }
 
 }  // namespace dart