Do-not-commit: Count layout tree memory usage

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

 // Copyright 2014 The Chromium 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 LayoutPagedFlowThread_h
 #define LayoutPagedFlowThread_h
 
 #include "core/layout/LayoutMultiColumnFlowThread.h"
 
 namespace blink {
@@ skipping 15 matching lines @@
 
   // Return the number of pages. Will never be less than 1.
   int pageCount();
 
   bool isLayoutPagedFlowThread() const override { return true; }
   const char* name() const override { return "LayoutPagedFlowThread"; }
   bool needsNewWidth() const override;
   void updateLogicalWidth() override;
   virtual void layout();
 
+  char objectSize() const override { return sizeof(this); }
+
  private:
   bool descendantIsValidColumnSpanner(
       LayoutObject* /*descendant*/) const override {
     return false;
   }
 };
 
 }  // namespace blink
 
 #endif  // LayoutPagedFlowThread_h