Replace RenderArena with PartitionAlloc.

Source/core/rendering/LayoutState.h

Index: Source/core/rendering/LayoutState.h
diff --git a/Source/core/rendering/LayoutState.h b/Source/core/rendering/LayoutState.h
index 3f2fe56496760d88c490e24554bc2b96c613a316..3f7d520279823cad27bf8cf99a08514180840de3 100644
--- a/Source/core/rendering/LayoutState.h
+++ b/Source/core/rendering/LayoutState.h
@@ -33,7 +33,6 @@
 
 namespace WebCore {
 
-class RenderArena;
 class RenderBlock;
 class RenderBox;
 class RenderObject;
@@ -65,13 +64,11 @@ public:
     LayoutState(LayoutState*, RenderBox*, const LayoutSize& offset, LayoutUnit pageHeight, bool pageHeightChanged, ColumnInfo*);
     LayoutState(RenderObject*);
 
-    void destroy(RenderArena*);
+    void destroy();
 
-    // Overloaded new operator.
-    void* operator new(size_t, RenderArena*);
-
-    // Overridden to prevent the normal delete from being called.
-    void operator delete(void*, size_t);
+#if ENABLE(PARTITION_ALLOC)
+    void* operator new(size_t);
+#endif
 
     void clearPaginationInformation();
     bool isPaginatingColumns() const { return m_columnInfo && m_columnInfo->paginationUnit() == ColumnInfo::Column; }
@@ -96,8 +93,9 @@ public:
 
     ExclusionShapeInsideInfo* exclusionShapeInsideInfo() const { return m_exclusionShapeInsideInfo; }
 private:
-    // The normal operator new is disallowed.
-    void* operator new(size_t) throw();
+#if ENABLE(PARTITION_ALLOC)
+    void operator delete(void*);
+#endif
 
     void propagateLineGridInfo(RenderBox*);
     void establishLineGrid(RenderBlock*);