New snapshot framework. Doesn't work on ARM yet (code targets...

src/objects.h

Index: src/objects.h
===================================================================
--- src/objects.h	(revision 3115)
+++ src/objects.h	(working copy)
@@ -1082,7 +1082,16 @@
   // View this map word as a forwarding address.
   inline HeapObject* ToForwardingAddress();
 
+  // True if this map word is a serialization address.  This will only be the
+  // case during a destructive serialization of the heap.
+  inline bool IsSerializationAddress();
 
+  // Create a map word from a serialization address.
+  static inline MapWord FromSerializationAddress(int raw);
+
+  // View this map word as a serialization address.
+  inline int ToSerializationAddress();
+
   // Marking phase of full collection: the map word of live objects is
   // marked, and may be marked as overflowed (eg, the object is live, its
   // children have not been visited, and it does not fit in the marking
@@ -5105,6 +5114,8 @@
   // Intended for serialization/deserialization checking: insert, or
   // check for the presence of, a tag at this position in the stream.
   virtual void Synchronize(const char* tag) {}
+#else
+  inline void Synchronize(const char* tag) {}
 #endif
 };