Remove CLASSHASH defines in favour of an enum class.

xfa/fwl/theme/cfwl_pushbuttontp.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_pushbuttontp.h"
 
 #include "xfa/fwl/basewidget/ifwl_pushbutton.h"
 #include "xfa/fwl/core/cfwl_themebackground.h"
 #include "xfa/fwl/core/ifwl_themeprovider.h"
 #include "xfa/fwl/core/ifwl_widget.h"
 #include "xfa/fxgraphics/cfx_color.h"
 #include "xfa/fxgraphics/cfx_path.h"
 
 #define PUSHBUTTON_SIZE_Corner 2
 
 CFWL_PushButtonTP::CFWL_PushButtonTP() : m_pThemeData(new PBThemeData) {
   SetThemeData(0);
 }
 
 CFWL_PushButtonTP::~CFWL_PushButtonTP() {
   delete m_pThemeData;
 }
 
-FX_BOOL CFWL_PushButtonTP::IsValidWidget(IFWL_Widget* pWidget) {
-  return pWidget->GetClassID() == FWL_CLASSHASH_PushButton;
+bool CFWL_PushButtonTP::IsValidWidget(IFWL_Widget* pWidget) {
+  return pWidget && pWidget->GetClassID() == FWL_Type::PushButton;
 }
 uint32_t CFWL_PushButtonTP::SetThemeID(IFWL_Widget* pWidget,
                                        uint32_t dwThemeID,
                                        FX_BOOL bChildren) {
   SetThemeData(FWL_GetThemeColor(dwThemeID));
   return CFWL_WidgetTP::SetThemeID(pWidget, dwThemeID, bChildren);
 }
 FX_BOOL CFWL_PushButtonTP::DrawBackground(CFWL_ThemeBackground* pParams) {
   switch (pParams->m_iPart) {
     case CFWL_Part::Border: {
@@ skipping 124 matching lines @@
   if (dwStates & CFWL_PartState_Default) {
     color += 3;
   } else {
     if (dwStates & CFWL_PartState_Hovered)
       color += 2;
     if (dwStates & CFWL_PartState_Pressed)
       color += 1;
   }
   return color;
 }