Fix two bugs in the code compaction:

src/frames.cc

 // Copyright 2011 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 1144 matching lines @@
 // -------------------------------------------------------------------------
 
 
 Code* PcToCodeCache::GcSafeCastToCode(HeapObject* object, Address pc) {
   Code* code = reinterpret_cast<Code*>(object);
   ASSERT(code != NULL && code->contains(pc));
   return code;
 }
 
 
+static int GcSafeSizeOfCodeSpaceObject(HeapObject* object) {
+  MapWord map_word = object->map_word();
+  Map* map = map_word.IsForwardingAddress() ?
+      map_word.ToForwardingAddress()->map() : map_word.ToMap();
+  return object->SizeFromMap(map);
+}
+
+
 Code* PcToCodeCache::GcSafeFindCodeForPc(Address pc) {
   Heap* heap = isolate_->heap();
   // Check if the pc points into a large object chunk.
   LargePage* large_page = heap->lo_space()->FindPageContainingPc(pc);
   if (large_page != NULL) return GcSafeCastToCode(large_page->GetObject(), pc);
 
   // Iterate through the page until we reach the end or find an object starting
   // after the pc.
   Page* page = Page::FromAddress(pc);
-  HeapObjectIterator iterator(page, heap->GcSafeSizeOfOldObjectFunction());
+  HeapObjectIterator iterator(page, &GcSafeSizeOfCodeSpaceObject);
   HeapObject* previous = NULL;
   while (true) {
     HeapObject* next = iterator.Next();
     if (next == NULL || next->address() >= pc) {
       return GcSafeCastToCode(previous, pc);
     }
     previous = next;
   }
 }
 
@@ skipping 85 matching lines @@
   ZoneList<StackFrame*> list(10);
   for (StackFrameIterator it; !it.done(); it.Advance()) {
     StackFrame* frame = AllocateFrameCopy(it.frame());
     list.Add(frame);
   }
   return list.ToVector();
 }
 
 
 } }  // namespace v8::internal