Introduce first approximation of constructor heap profile for JS objects.

src/spaces.h

 // Copyright 2006-2008 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 913 matching lines @@
 #ifdef DEBUG
   // Returns the number of total pages in this space.
   int CountTotalPages();
 #endif
 
   friend class PageIterator;
 };
 
 
 #if defined(DEBUG) || defined(ENABLE_LOGGING_AND_PROFILING)
-// HistogramInfo class for recording a single "bar" of a histogram.  This
-// class is used for collecting statistics to print to stdout (when compiled
-// with DEBUG) or to the log file (when compiled with
-// ENABLE_LOGGING_AND_PROFILING).
-class HistogramInfo BASE_EMBEDDED {
+class NumberAndSizeInfo BASE_EMBEDDED {
  public:
-  HistogramInfo() : number_(0), bytes_(0) {}
+  NumberAndSizeInfo() : number_(0), bytes_(0) {}
 
-  const char* name() { return name_; }
-  void set_name(const char* name) { name_ = name; }
-
-  int number() { return number_; }
+  int number() const { return number_; }
   void increment_number(int num) { number_ += num; }
 
-  int bytes() { return bytes_; }
+  int bytes() const { return bytes_; }
   void increment_bytes(int size) { bytes_ += size; }
 
-  // Clear the number of objects and size fields, but not the name.
   void clear() {
     number_ = 0;
     bytes_ = 0;
   }
 
  private:
-  const char* name_;
   int number_;
   int bytes_;
 };
+
+
+// HistogramInfo class for recording a single "bar" of a histogram.  This
+// class is used for collecting statistics to print to stdout (when compiled
+// with DEBUG) or to the log file (when compiled with
+// ENABLE_LOGGING_AND_PROFILING).
+class HistogramInfo: public NumberAndSizeInfo {
+ public:
+  HistogramInfo() : NumberAndSizeInfo() {}
+
+  const char* name() { return name_; }
+  void set_name(const char* name) { name_ = name; }
+
+ private:
+  const char* name_;
+};
 #endif
 
 
 // -----------------------------------------------------------------------------
 // SemiSpace in young generation
 //
 // A semispace is a contiguous chunk of memory. The mark-compact collector
 // uses the memory in the from space as a marking stack when tracing live
 // objects.
 
@@ skipping 827 matching lines @@
 
  private:
   LargeObjectChunk* current_;
   HeapObjectCallback size_func_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_SPACES_H_