[Isolates] Add a pointer to Heap to a meta map.

src/serialize.cc

Index: src/serialize.cc
diff --git a/src/serialize.cc b/src/serialize.cc
index d37ebbe72c9ca6c0a23e096cced976e767b47a75..c26b3b99254da8c65402adb31ccf6cdc5afa2f64 100644
--- a/src/serialize.cc
+++ b/src/serialize.cc
@@ -691,8 +691,14 @@ void Deserializer::ReadObject(int space_number,
     ASSERT(size == Map::kSize);
     HeapObject* obj = HeapObject::FromAddress(address);
     Map* map = reinterpret_cast<Map*>(obj);
-    map->set_scavenger(Heap::GetScavenger(map->instance_type(),
-                                          map->instance_size()));
+    if (map->instance_type() == MAP_TYPE) {
+      // Meta map has Heap pointer instead of scavenger.
+      ASSERT(map == map->map());
+      map->set_heap(HEAP);
+    } else {
+      map->set_scavenger(Heap::GetScavenger(map->instance_type(),
+                                            map->instance_size()));
+    }
   }
 }