Replace RenderArena with PartitionAlloc.

Source/core/rendering/BidiRun.h

Index: Source/core/rendering/BidiRun.h
diff --git a/Source/core/rendering/BidiRun.h b/Source/core/rendering/BidiRun.h
index c4c266f53aada16ff5c66b77fb10ec1962202c84..f4409cf141f88bb3a01fd871114bc8a980f19640 100644
--- a/Source/core/rendering/BidiRun.h
+++ b/Source/core/rendering/BidiRun.h
@@ -46,18 +46,17 @@ struct BidiRun : BidiCharacterRun {
 
     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
 
     BidiRun* next() { return static_cast<BidiRun*>(m_next); }
     RenderObject* object() { return m_object; }
 
 private:
-    // The normal operator new is disallowed.
-    void* operator new(size_t) throw();
+#if ENABLE(PARTITION_ALLOC)
+    void operator delete(void*);
+#endif
 
 public:
     RenderObject* m_object;