[heap] Rework and improve object stats tracing

src/heap/mark-compact.h

 // Copyright 2012 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.
 
 #ifndef V8_HEAP_MARK_COMPACT_H_
 #define V8_HEAP_MARK_COMPACT_H_
 
 #include <deque>
 
 #include "src/base/bits.h"
@@ skipping 611 matching lines @@
 
   void RegisterExternallyReferencedObject(Object** object);
 
  private:
   class EvacuateNewSpacePageVisitor;
   class EvacuateNewSpaceVisitor;
   class EvacuateOldSpaceVisitor;
   class EvacuateRecordOnlyVisitor;
   class EvacuateVisitorBase;
   class HeapObjectVisitor;
+  class ObjectStatsVisitor;
 
   explicit MarkCompactCollector(Heap* heap);
 
   bool WillBeDeoptimized(Code* code);
   void ClearInvalidRememberedSetSlots();
 
   void ComputeEvacuationHeuristics(int area_size,
                                    int* target_fragmentation_percent,
                                    int* max_evacuated_bytes);
 
+  void VisitAllObjects(HeapObjectVisitor* visitor);
+
   // Finishes GC, performs heap verification if enabled.
   void Finish();
 
   // -----------------------------------------------------------------------
   // Phase 1: Marking live objects.
   //
   //  Before: The heap has been prepared for garbage collection by
   //          MarkCompactCollector::Prepare() and is otherwise in its
   //          normal state.
   //
@@ skipping 234 matching lines @@
  private:
   MarkCompactCollector* collector_;
 };
 
 
 const char* AllocationSpaceName(AllocationSpace space);
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_MARK_COMPACT_H_