Don't explicitly initialize LayoutUnit to 0.

third_party/WebKit/Source/core/layout/LayoutGrid.cpp

 /*
  * Copyright (C) 2011 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 25 matching lines @@
 
 namespace blink {
 
 static const int infinity = -1;
 
 class GridItemWithSpan;
 
 class GridTrack {
 public:
     GridTrack()
-        : m_baseSize(0)
-        , m_growthLimit(0)
-        , m_plannedSize(0)
-        , m_sizeDuringDistribution(0)
-        , m_infinitelyGrowable(false)
+        : m_infinitelyGrowable(false)
     {
     }
 
     const LayoutUnit& baseSize() const
     {
         ASSERT(isGrowthLimitBiggerThanBaseSize());
         return m_baseSize;
     }
 
     const LayoutUnit& growthLimit() const
@@ skipping 2171 matching lines @@
 
     return LayoutPoint(rowAxisOffset, columnAxisOffsetForChild(child, sizingData));
 }
 
 void LayoutGrid::paintChildren(const PaintInfo& paintInfo, const LayoutPoint& paintOffset) const
 {
     GridPainter(*this).paintChildren(paintInfo, paintOffset);
 }
 
 } // namespace blink