Extern in .cpp file is a code smell, part 2.

core/src/fpdfapi/fpdf_parser/fpdf_parser_document.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 "../../../include/fpdfapi/fpdf_parser.h"
 #include "../../../include/fpdfapi/fpdf_module.h"
 
 CPDF_Document::CPDF_Document(CPDF_Parser* pParser)
@@ skipping 68 matching lines @@
     m_dwFirstPageNo = pNo->GetInteger();
   }
   CPDF_Object* pObjNum = pLinearized->GetElement(FX_BSTRC("O"));
   if (pObjNum && pObjNum->GetType() == PDFOBJ_NUMBER) {
     m_dwFirstPageObjNum = pObjNum->GetInteger();
   }
 }
 void CPDF_Document::LoadPages() {
   m_PageList.SetSize(_GetPageCount());
 }
-extern void FPDF_TTFaceMapper_ReleaseDoc(CPDF_Document*);
 CPDF_Document::~CPDF_Document() {
   if (m_pDocPage) {
     CPDF_ModuleMgr::Get()->GetPageModule()->ReleaseDoc(this);
     CPDF_ModuleMgr::Get()->GetPageModule()->ClearStockFont(this);
   }
   if (m_pDocRender) {
     CPDF_ModuleMgr::Get()->GetRenderModule()->DestroyDocData(m_pDocRender);
   }
 }
 #define FX_MAX_PAGE_LEVEL 1024
@@ skipping 252 matching lines @@
 void CPDF_Document::ClearPageData() {
   if (m_pDocPage) {
     CPDF_ModuleMgr::Get()->GetPageModule()->ClearDoc(this);
   }
 }
 void CPDF_Document::ClearRenderData() {
   if (m_pDocRender) {
     CPDF_ModuleMgr::Get()->GetRenderModule()->ClearDocData(m_pDocRender);
   }
 }