Do-not-commit: Count layout tree memory usage

third_party/WebKit/Source/core/layout/LayoutTableSection.h

 /*
  * Copyright (C) 1997 Martin Jones (mjones@kde.org)
  *           (C) 1997 Torben Weis (weis@kde.org)
  *           (C) 1998 Waldo Bastian (bastian@kde.org)
  *           (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2009, 2013 Apple Inc. All rights
  * reserved.
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 290 matching lines @@
   LayoutRect logicalRectForWritingModeAndDirection(const LayoutRect&) const;
 
   CellSpan dirtiedRows(const LayoutRect& visualRect) const;
   CellSpan dirtiedEffectiveColumns(const LayoutRect& visualRect) const;
   const HashSet<LayoutTableCell*>& overflowingCells() const {
     return m_overflowingCells;
   }
   bool hasMultipleCellLevels() const { return m_hasMultipleCellLevels; }
 
   const char* name() const override { return "LayoutTableSection"; }
+  char objectSize() const override { return sizeof(this); }
+  char approximateHeapMemoryUsage() const override {
+    // TODO(pdr): Include additional heap allocations in this class.
+    return LayoutTableBoxComponent::approximateHeapMemoryUsage();
+  }
 
   // Whether a section has opaque background depends on many factors, e.g.
   // border spacing, border collapsing, missing cells, etc. For simplicity,
   // just conservatively assume all table sections are not opaque.
   bool foregroundIsKnownToBeOpaqueInRect(const LayoutRect&,
                                          unsigned) const override {
     return false;
   }
   bool backgroundIsKnownToBeOpaqueInRect(const LayoutRect&) const override {
     return false;
@@ skipping 154 matching lines @@
   // The use is to disable a painting optimization where we just paint the
   // invalidated cells.
   bool m_hasMultipleCellLevels;
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutTableSection, isTableSection());
 
 }  // namespace blink
 
 #endif  // LayoutTableSection_h