Convert XFA_ELEMENT to an enum class

xfa/fxfa/parser/cxfa_line.cpp

 // Copyright 2016 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "xfa/fxfa/parser/cxfa_line.h"
 
 #include "xfa/fxfa/parser/xfa_object.h"
 
 int32_t CXFA_Line::GetHand() {
   return m_pNode->GetEnum(XFA_ATTRIBUTE_Hand);
 }
 
 FX_BOOL CXFA_Line::GetSlop() {
   XFA_ATTRIBUTEENUM eSlop = m_pNode->GetEnum(XFA_ATTRIBUTE_Slope);
   return eSlop == XFA_ATTRIBUTEENUM_Slash;
 }
 
 CXFA_Edge CXFA_Line::GetEdge() {
-  return CXFA_Edge(m_pNode->GetChild(0, XFA_ELEMENT_Edge));
+  return CXFA_Edge(m_pNode->GetChild(0, XFA_Element::Edge));
 }