Remove CLASSHASH defines in favour of an enum class.

xfa/fwl/theme/cfwl_formtp.cpp

 // Copyright 2014 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/fwl/theme/cfwl_formtp.h"
 
 #include "xfa/fde/tto/fde_textout.h"
 #include "xfa/fwl/core/cfwl_themebackground.h"
@@ skipping 42 matching lines @@
 
 FWL_Error CFWL_FormTP::Finalize() {
   FinalizeTTO();
   delete m_pActiveBitmap;
   m_pActiveBitmap = nullptr;
   delete m_pDeactivebitmap;
   m_pDeactivebitmap = nullptr;
   return CFWL_WidgetTP::Finalize();
 }
 
-FX_BOOL CFWL_FormTP::IsValidWidget(IFWL_Widget* pWidget) {
-  if (!pWidget)
-    return FALSE;
-  uint32_t dwHash = pWidget->GetClassID();
-  return dwHash == FWL_CLASSHASH_Form;
+bool CFWL_FormTP::IsValidWidget(IFWL_Widget* pWidget) {
+  return pWidget && pWidget->GetClassID() == FWL_Type::Form;
 }
+
 uint32_t CFWL_FormTP::SetThemeID(IFWL_Widget* pWidget,
                                  uint32_t dwThemeID,
                                  FX_BOOL bChildren) {
   if (m_pThemeData) {
     SetThemeData(FWL_GetThemeColor(dwThemeID));
   }
   InitCaption(TRUE);
   InitCaption(FALSE);
   return CFWL_WidgetTP::SetThemeID(pWidget, dwThemeID, bChildren);
 }
@@ skipping 796 matching lines @@
     path.Clear();
     path.AddRectangle(0, 5, 1, 15);
     DrawAxialShading(&gs, 0, 5, 0, 20, m_pThemeData->clrHeadBK[1][1],
                      m_pThemeData->clrHeadBK[1][2], &path);
     path.Clear();
     path.AddRectangle(0, 20, 1, kCYCaption - 19);
     DrawAxialShading(&gs, 0, 20, 0, kCYCaption, m_pThemeData->clrHeadBK[1][2],
                      m_pThemeData->clrHeadBK[1][3], &path);
   }
 }