Make CPDF_Object::GetString() a virtual method.

core/src/fpdfapi/fpdf_edit/fpdf_edit_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 "../../../include/fpdfapi/fpdf_page.h"
 #include "../../../include/fpdfapi/fpdf_module.h"
 #include "../fpdf_page/pageint.h"
 #include <limits.h>
@@ skipping 1042 matching lines @@
 static int InsertDeletePDFPage(CPDF_Document* pDoc, CPDF_Dictionary* pPages,
                                int nPagesToGo, CPDF_Dictionary* pPage, FX_BOOL bInsert, CFX_PtrArray& stackList)
 {
     CPDF_Array* pKidList = pPages->GetArray("Kids");
     if (!pKidList) {
         return -1;
     }
     int nKids = pKidList->GetCount();
     for (int i = 0; i < nKids; i ++) {
         CPDF_Dictionary* pKid = pKidList->GetDict(i);
-        if (pKid->GetString("Type") == FX_BSTRC("Page")) {
+        if (pKid->GetStringAt("Type") == "Page") {
             if (nPagesToGo == 0) {
                 if (bInsert) {
                     pKidList->InsertAt(i, CPDF_Reference::Create(pDoc, pPage->GetObjNum()));
                     pPage->SetAtReference("Parent", pDoc, pPages->GetObjNum());
                 } else {
                     pKidList->RemoveAt(i);
                 }
                 pPages->SetAtInteger("Count", pPages->GetInteger("Count") + (bInsert ? 1 : -1));
                 return 1;
             }
@@ skipping 98 matching lines @@
 void FPDFAPI_FlatPageAttr(CPDF_Dictionary* pPageDict, const CFX_ByteStringC& name)
 {
     if (pPageDict->KeyExist(name)) {
         return;
     }
     CPDF_Object* pObj = FPDFAPI_GetPageAttr(pPageDict, name);
     if (pObj) {
         pPageDict->SetAt(name, pObj->Clone());
     }
 }