refactor CPDF_Font and subclasses

core/src/fpdfapi/fpdf_page/fpdf_page_doc.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 "core/src/fpdfapi/fpdf_page/pageint.h"
 
 #include "core/include/fdrm/fx_crypt.h"
 #include "core/include/fpdfapi/fpdf_module.h"
@@ skipping 243 matching lines @@
 
   for (auto& it : m_FontMap) {
     CPDF_CountedFont* fontData = it.second;
     CPDF_Font* pFont = fontData->get();
     if (!pFont)
       continue;
     if (pFont->GetBaseFont() != fontName)
       continue;
     if (pFont->IsEmbedded())
       continue;
-    if (pFont->GetFontType() != PDFFONT_TYPE1)
+    if (!pFont->IsType1Font())
       continue;
     if (pFont->GetFontDict()->KeyExist("Widths"))
       continue;
 
-    CPDF_Type1Font* pT1Font = pFont->GetType1Font();
+    CPDF_Type1Font* pT1Font = pFont->AsType1Font();
     if (pEncoding && !pT1Font->GetEncoding()->IsIdentical(pEncoding))
       continue;
 
     return fontData->AddRef();
   }
 
   CPDF_Dictionary* pDict = new CPDF_Dictionary;
   pDict->SetAtName("Type", "Font");
   pDict->SetAtName("Subtype", "Type1");
   pDict->SetAtName("BaseFont", fontName);
@@ skipping 318 matching lines @@
 }
 
 CPDF_CountedPattern* CPDF_DocPageData::FindPatternPtr(
     CPDF_Object* pPatternObj) const {
   if (!pPatternObj)
     return nullptr;
 
   auto it = m_PatternMap.find(pPatternObj);
   return it != m_PatternMap.end() ? it->second : nullptr;
 }