Allow smis for singleton types

src/objects-debug.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 760 matching lines @@
 
   VerifyPointer(elements());
 }
 
 
 void Foreign::ForeignVerify() {
   CHECK(IsForeign());
 }
 
 
+void Box::BoxVerify() {
+  CHECK(IsBox());
+  value()->Verify();
+}
+
+
 void AccessorInfo::AccessorInfoVerify() {
   VerifyPointer(name());
   VerifyPointer(flag());
   VerifyPointer(expected_receiver_type());
 }
 
 
 void ExecutableAccessorInfo::ExecutableAccessorInfoVerify() {
   CHECK(IsExecutableAccessorInfo());
   AccessorInfoVerify();
@@ skipping 329 matching lines @@
   for (int i = 0; i < number_of_transitions(); ++i) {
     if (!CheckOneBackPointer(current_map, GetTarget(i))) return false;
   }
   return true;
 }
 
 
 #endif  // DEBUG
 
 } }  // namespace v8::internal