Use enum class for subtypes of CPDF_Annot.

fpdfsdk/cpdfsdk_xfawidgethandler.cpp

Index: fpdfsdk/cpdfsdk_xfawidgethandler.cpp
diff --git a/fpdfsdk/cpdfsdk_xfawidgethandler.cpp b/fpdfsdk/cpdfsdk_xfawidgethandler.cpp
index 9a9a7a8a4a9be1396b388881fc808ef745c8bedf..59fa5c72416b0a924055a33c0154679e8e30efc0 100644
--- a/fpdfsdk/cpdfsdk_xfawidgethandler.cpp
+++ b/fpdfsdk/cpdfsdk_xfawidgethandler.cpp
@@ -25,10 +25,6 @@ CPDFSDK_XFAWidgetHandler::CPDFSDK_XFAWidgetHandler(CPDFDoc_Environment* pApp)
 
 CPDFSDK_XFAWidgetHandler::~CPDFSDK_XFAWidgetHandler() {}
 
-CFX_ByteString CPDFSDK_XFAWidgetHandler::GetType() {
-  return FSDK_XFAWIDGET_TYPENAME;
-}
-
 FX_BOOL CPDFSDK_XFAWidgetHandler::CanAnswer(CPDFSDK_Annot* pAnnot) {
   return !!pAnnot->GetXFAWidget();
 }