Don't explicitly initialize LayoutUnit to 0.

third_party/WebKit/Source/core/layout/line/RootInlineBox.cpp

 /*
  * Copyright (C) 2003, 2006, 2008 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 32 matching lines @@
 
 static_assert(sizeof(RootInlineBox) == sizeof(SameSizeAsRootInlineBox), "RootInlineBox should stay small");
 
 typedef WTF::HashMap<const RootInlineBox*, EllipsisBox*> EllipsisBoxMap;
 static EllipsisBoxMap* gEllipsisBoxMap = nullptr;
 
 RootInlineBox::RootInlineBox(LineLayoutItem block)
     : InlineFlowBox(block)
     , m_lineBreakPos(0)
     , m_lineBreakObj(nullptr)
-    , m_lineTop(0)
-    , m_lineBottom(0)
-    , m_lineTopWithLeading(0)
-    , m_lineBottomWithLeading(0)
-    , m_selectionBottom(0)
-    , m_paginationStrut(0)
 {
     setIsHorizontal(block.isHorizontalWritingMode());
 }
 
 void RootInlineBox::destroy()
 {
     detachEllipsisBox();
     InlineFlowBox::destroy();
 }
 
@@ skipping 639 matching lines @@
     endBox = nullptr;
     return nullptr;
 }
 
 const char* RootInlineBox::boxName() const
 {
     return "RootInlineBox";
 }
 
 } // namespace blink