Use enum class for subtypes of CPDF_Annot.

fpdfsdk/cpdfsdk_bfannothandler.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 "fpdfsdk/include/cpdfsdk_bfannothandler.h"
 
 #include <memory>
 #include <vector>
@@ skipping 14 matching lines @@
 CPDFSDK_BFAnnotHandler::CPDFSDK_BFAnnotHandler(CPDFDoc_Environment* pApp)
     : m_pApp(pApp), m_pFormFiller(nullptr) {}
 
 CPDFSDK_BFAnnotHandler::~CPDFSDK_BFAnnotHandler() {}
 
 CFX_ByteString CPDFSDK_BFAnnotHandler::GetType() {
   return CFX_ByteString("Widget");
 }
 
 FX_BOOL CPDFSDK_BFAnnotHandler::CanAnswer(CPDFSDK_Annot* pAnnot) {
-  ASSERT(pAnnot->GetAnnotSubtype() == "Widget");
+  ASSERT(pAnnot->GetAnnotSubtype() == CPDF_Annot::Subtype::WIDGET);
   if (pAnnot->IsSignatureWidget())
     return FALSE;
 
   CPDFSDK_Widget* pWidget = static_cast<CPDFSDK_Widget*>(pAnnot);
   if (!pWidget->IsVisible())
     return FALSE;
 
   int nFieldFlags = pWidget->GetFieldFlags();
   if ((nFieldFlags & FIELDFLAG_READONLY) == FIELDFLAG_READONLY)
     return FALSE;
@@ skipping 256 matching lines @@
 
 FX_BOOL CPDFSDK_BFAnnotHandler::HitTest(CPDFSDK_PageView* pPageView,
                                         CPDFSDK_Annot* pAnnot,
                                         const CFX_FloatPoint& point) {
   ASSERT(pPageView);
   ASSERT(pAnnot);
 
   CFX_FloatRect rect = GetViewBBox(pPageView, pAnnot);
   return rect.Contains(point.x, point.y);
 }