Do-not-commit: Count layout tree memory usage

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

 /*
  * (C) 1999 Lars Knoll (knoll@kde.org)
  * (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 32 matching lines @@
   LayoutTextFragment(Node*, StringImpl*);
   ~LayoutTextFragment() override;
 
   static LayoutTextFragment* createAnonymous(PseudoElement&, StringImpl*);
   static LayoutTextFragment* createAnonymous(PseudoElement&,
                                              StringImpl*,
                                              unsigned start,
                                              unsigned length);
 
   bool isTextFragment() const override { return true; }
+  char objectSize() const override { return sizeof(this); }
+  char approximateHeapMemoryUsage() const override {
+    int memory = LayoutText::approximateHeapMemoryUsage();
+    // TODO(pdr): Include memory from m_contentString?
+    return memory;
+  }
 
   bool canBeSelectionLeaf() const override {
     return node() && hasEditableStyle(*node());
   }
 
   unsigned start() const { return m_start; }
   unsigned fragmentLength() const { return m_fragmentLength; }
 
   unsigned textStartOffset() const override { return start(); }
 
@@ skipping 50 matching lines @@
 
 DEFINE_TYPE_CASTS(LayoutTextFragment,
                   LayoutObject,
                   object,
                   toLayoutText(object)->isTextFragment(),
                   toLayoutText(object).isTextFragment());
 
 }  // namespace blink
 
 #endif  // LayoutTextFragment_h