Make embedded maps in optimized code weak.

src/mark-compact.h

Index: src/mark-compact.h
diff --git a/src/mark-compact.h b/src/mark-compact.h
index b34be6b91daabf696440b607e23a8c7532859130..08379591872b291955f46180fa602e2186bdae2b 100644
--- a/src/mark-compact.h
+++ b/src/mark-compact.h
@@ -797,10 +797,13 @@ class MarkCompactCollector {
 
   // Map transitions from a live map to a dead map must be killed.
   // We replace them with a null descriptor, with the same key.
-  void ClearNonLiveTransitions();
+  void ClearNonLiveReferences();
   void ClearNonLivePrototypeTransitions(Map* map);
   void ClearNonLiveMapTransitions(Map* map, MarkBit map_mark);
 
+  void ClearAndDeoptimizeDependentCodes(Map* map);
+  void ClearNonLiveDependentCodes(Map* map);
+
   // Marking detaches initial maps from SharedFunctionInfo objects
   // to make this reference weak. We need to reattach initial maps
   // back after collection. This is either done during