Generalize virtually dispatched scavenger to virtually dispatched specialized visitors.

src/factory.cc

Index: src/factory.cc
diff --git a/src/factory.cc b/src/factory.cc
index d65338385e08111fc06b51309d859249ef17973f..690ac609cb720d3a6cb16d41f44d6db69c5390ab 100644
--- a/src/factory.cc
+++ b/src/factory.cc
@@ -32,6 +32,7 @@
 #include "execution.h"
 #include "factory.h"
 #include "macro-assembler.h"
+#include "objects-visiting.h"
 
 namespace v8 {
 namespace internal {
@@ -277,8 +278,7 @@ Handle<Map> Factory::CopyMap(Handle<Map> src,
   copy->set_inobject_properties(inobject_properties);
   copy->set_unused_property_fields(inobject_properties);
   copy->set_instance_size(copy->instance_size() + instance_size_delta);
-  copy->set_scavenger(Heap::GetScavenger(copy->instance_type(),
-                                         copy->instance_size()));
+  copy->set_visitor_id(StaticVisitorBase::GetVisitorId(*copy));
   return copy;
 }