[serializer] remove some dead code.

test/cctest/test-serialize.cc

 // Copyright 2007-2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 75 matching lines @@
     i::PrintF("Writing snapshot file failed.. Aborting.\n");
     exit(1);
   }
   fclose(file);
 }
 
 
 static bool WriteToFile(Isolate* isolate, const char* snapshot_file) {
   SnapshotByteSink sink;
   StartupSerializer ser(isolate, &sink);
-  ser.Serialize();
+  ser.SerializeStrongReferences();
+  ser.SerializeWeakReferencesAndDeferred();
   SnapshotData snapshot_data(ser);
   WritePayload(snapshot_data.RawData(), snapshot_file);
   return true;
 }
 
 
 static void Serialize(v8::Isolate* isolate) {
   // We have to create one context.  One reason for this is so that the builtins
   // can be loaded from v8natives.js and their addresses can be processed.  This
   // will clear the pending fixups array, which would otherwise contain GC roots
@@ skipping 1657 matching lines @@
   delete script_data;
 }
 
 
 TEST(SerializationMemoryStats) {
   FLAG_profile_deserialization = true;
   FLAG_always_opt = false;
   v8::StartupData blob = v8::V8::CreateSnapshotDataBlob();
   delete[] blob.data;
 }