Move m_pageLogicalOffset from LayoutBlock to LayoutBoxRareData.

Source/core/layout/LayoutBox.cpp

Index: Source/core/layout/LayoutBox.cpp
diff --git a/Source/core/layout/LayoutBox.cpp b/Source/core/layout/LayoutBox.cpp
index 3fe7409b4b57cf3135ad63f77991de306704d548..78cc863c00f7c60c6398c8324003374d91bb8047 100644
--- a/Source/core/layout/LayoutBox.cpp
+++ b/Source/core/layout/LayoutBox.cpp
@@ -4654,6 +4654,13 @@ LayoutUnit LayoutBox::offsetFromLogicalTopOfFirstPage() const
     return containerBlock->offsetFromLogicalTopOfFirstPage() + logicalTop();
 }
 
+void LayoutBox::setPageLogicalOffset(LayoutUnit offset)
+{
+    if (!m_rareData && !offset)
+        return;
+    ensureRareData().m_pageLogicalOffset = offset;
+}
+
 void LayoutBox::savePreviousBorderBoxSizeIfNeeded()
 {
     // If m_rareData is already created, always save.