[CSS Grid Layout] Add support to place items using named grid lines

Source/core/rendering/style/StyleGridData.cpp

Index: Source/core/rendering/style/StyleGridData.cpp
diff --git a/Source/core/rendering/style/StyleGridData.cpp b/Source/core/rendering/style/StyleGridData.cpp
index d323864b32bdb1b9614b7712c3f56fa713a2ee24..bb942232d23dff86f13ce89f25b6ac8304db5a7f 100644
--- a/Source/core/rendering/style/StyleGridData.cpp
+++ b/Source/core/rendering/style/StyleGridData.cpp
@@ -33,8 +33,6 @@ namespace WebCore {
 StyleGridData::StyleGridData()
     : m_gridTemplateColumns(RenderStyle::initialGridTemplateColumns())
     , m_gridTemplateRows(RenderStyle::initialGridTemplateRows())
-    , m_namedGridColumnLines(RenderStyle::initialNamedGridColumnLines())
-    , m_namedGridRowLines(RenderStyle::initialNamedGridRowLines())
     , m_orderedNamedGridColumnLines(RenderStyle::initialOrderedNamedGridColumnLines())
     , m_orderedNamedGridRowLines(RenderStyle::initialOrderedNamedGridRowLines())
     , m_gridAutoFlow(RenderStyle::initialGridAutoFlow())
@@ -50,8 +48,6 @@ StyleGridData::StyleGridData(const StyleGridData& o)
     : RefCounted<StyleGridData>()
     , m_gridTemplateColumns(o.m_gridTemplateColumns)
     , m_gridTemplateRows(o.m_gridTemplateRows)
-    , m_namedGridColumnLines(o.m_namedGridColumnLines)
-    , m_namedGridRowLines(o.m_namedGridRowLines)
     , m_orderedNamedGridColumnLines(o.m_orderedNamedGridColumnLines)
     , m_orderedNamedGridRowLines(o.m_orderedNamedGridRowLines)
     , m_gridAutoFlow(o.m_gridAutoFlow)