Remove CLASSHASH defines in favour of an enum class.

xfa/fwl/theme/cfwl_listboxtp.cpp

Index: xfa/fwl/theme/cfwl_listboxtp.cpp
diff --git a/xfa/fwl/theme/cfwl_listboxtp.cpp b/xfa/fwl/theme/cfwl_listboxtp.cpp
index 5bab1b09e5d608fa341b0879c7a3a508e2f44b21..1d381a42804f1b54b99968d2af2cec5e4db02be6 100644
--- a/xfa/fwl/theme/cfwl_listboxtp.cpp
+++ b/xfa/fwl/theme/cfwl_listboxtp.cpp
@@ -13,13 +13,13 @@
 #include "xfa/fxgraphics/cfx_path.h"
 
 CFWL_ListBoxTP::CFWL_ListBoxTP() {}
+
 CFWL_ListBoxTP::~CFWL_ListBoxTP() {}
 
-FX_BOOL CFWL_ListBoxTP::IsValidWidget(IFWL_Widget* pWidget) {
-  if (!pWidget)
-    return FALSE;
-  return pWidget->GetClassID() == FWL_CLASSHASH_ListBox;
+bool CFWL_ListBoxTP::IsValidWidget(IFWL_Widget* pWidget) {
+  return pWidget && pWidget->GetClassID() == FWL_Type::ListBox;
 }
+
 FX_BOOL CFWL_ListBoxTP::DrawBackground(CFWL_ThemeBackground* pParams) {
   if (!pParams)
     return FALSE;