Do-not-commit: Count layout tree memory usage

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

 /*
  * Copyright (C) 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google Inc. 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.
@@ skipping 29 matching lines @@
 
 // FIXME: Find a way to cascade appearance and adjust heights, and get rid of
 // this class. See http://webkit.org/b/62535
 class LayoutSliderContainer final : public LayoutFlexibleBox {
  public:
   LayoutSliderContainer(SliderContainerElement*);
   void computeLogicalHeight(LayoutUnit logicalHeight,
                             LayoutUnit logicalTop,
                             LogicalExtentComputedValues&) const override;
 
+  char objectSize() const override { return sizeof(this); }
+
  private:
   void layout() override;
 };
 
 }  // namespace blink
 
 #endif  // LayoutSliderContainer_h