Fix 64 bit build. TBR=ager.

Review URL: http://codereview.chromium.org/442003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3361 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/serialize.cc

@@ -55,7 +55,7 @@ class SerializationAddressMapper {
 
   static int MappedTo(HeapObject* obj) {
     ASSERT(IsMapped(obj));
-    return reinterpret_cast<int>(serialization_map_->Lookup(Key(obj),
+    return reinterpret_cast<intptr_t>(serialization_map_->Lookup(Key(obj),
                                       Hash(obj),
                                       false)->value);
   }
@@ -81,7 +81,7 @@ class SerializationAddressMapper {
   }
 
   static uint32_t Hash(HeapObject* obj) {
-    return reinterpret_cast<uint32_t>(obj->address());
+    return reinterpret_cast<intptr_t>(obj->address());
   }
 
   static void* Key(HeapObject* obj) {