Inobject slack tracking is done on a per-closure basis instead of per-shared info basis.

src/heap-snapshot-generator.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "v8.h"
 
 #include "heap-snapshot-generator-inl.h"
 
 #include "allocation-tracker.h"
 #include "code-stubs.h"
@@ skipping 1391 matching lines @@
                        SharedFunctionInfo::kDebugInfoOffset);
   SetInternalReference(obj, entry,
                        "inferred_name", shared->inferred_name(),
                        SharedFunctionInfo::kInferredNameOffset);
   SetInternalReference(obj, entry,
                        "optimized_code_map", shared->optimized_code_map(),
                        SharedFunctionInfo::kOptimizedCodeMapOffset);
   SetInternalReference(obj, entry,
                        "feedback_vector", shared->feedback_vector(),
                        SharedFunctionInfo::kFeedbackVectorOffset);
-  SetWeakReference(obj, entry,
-                   "initial_map", shared->initial_map(),
-                   SharedFunctionInfo::kInitialMapOffset);
 }
 
 
 void V8HeapExplorer::ExtractScriptReferences(int entry, Script* script) {
   HeapObject* obj = script;
   SetInternalReference(obj, entry,
                        "source", script->source(),
                        Script::kSourceOffset);
   SetInternalReference(obj, entry,
                        "name", script->name(),
@@ skipping 1724 matching lines @@
   writer_->AddString("\"<dummy>\"");
   for (int i = 1; i < sorted_strings.length(); ++i) {
     writer_->AddCharacter(',');
     SerializeString(sorted_strings[i]);
     if (writer_->aborted()) return;
   }
 }
 
 
 } }  // namespace v8::internal