Make CPDF_Object::GetString() a virtual method.

core/src/fpdfdoc/doc_basic.cpp

Index: core/src/fpdfdoc/doc_basic.cpp
diff --git a/core/src/fpdfdoc/doc_basic.cpp b/core/src/fpdfdoc/doc_basic.cpp
index 9d31d156245e844b51f82a1cc99636a875081de3..530a84b6810bec9ca805d4f68e7ab4a5471b65da 100644
--- a/core/src/fpdfdoc/doc_basic.cpp
+++ b/core/src/fpdfdoc/doc_basic.cpp
@@ -87,8 +87,8 @@ static CPDF_Object* SearchNameNode(CPDF_Dictionary* pNode, const CFX_ByteString&
     }
     CPDF_Array* pLimits = pNode->GetArray(FX_BSTRC("Limits"));
     if (pLimits != NULL) {
-        CFX_ByteString csLeft = pLimits->GetString(0);
-        CFX_ByteString csRight = pLimits->GetString(1);
+        CFX_ByteString csLeft = pLimits->GetStringAt(0);
+        CFX_ByteString csRight = pLimits->GetStringAt(1);
         if (csLeft.Compare(csRight) > 0) {
             CFX_ByteString csTmp = csRight;
             csRight = csLeft;
@@ -102,7 +102,7 @@ static CPDF_Object* SearchNameNode(CPDF_Dictionary* pNode, const CFX_ByteString&
     if (pNames) {
         FX_DWORD dwCount = pNames->GetCount() / 2;
         for (FX_DWORD i = 0; i < dwCount; i ++) {
-            CFX_ByteString csValue = pNames->GetString(i * 2);
+            CFX_ByteString csValue = pNames->GetStringAt(i * 2);
             int32_t iCompare = csValue.Compare(csName);
             if (iCompare <= 0) {
                 if (ppFind != NULL) {
@@ -152,7 +152,7 @@ static CPDF_Object* SearchNameNode(CPDF_Dictionary* pNode, int nIndex, int& nCur
             if (ppFind != NULL) {
                 *ppFind = pNames;
             }
-            csName = pNames->GetString((nIndex - nCurIndex) * 2);
+            csName = pNames->GetStringAt((nIndex - nCurIndex) * 2);
             return pNames->GetElementValue((nIndex - nCurIndex) * 2 + 1);
         }
     }
@@ -323,18 +323,21 @@ FX_BOOL CPDF_FileSpec::GetFileName(CFX_WideString &csFileName) const
         CPDF_Dictionary* pDict = (CPDF_Dictionary*)m_pObj;
         csFileName = pDict->GetUnicodeText(FX_BSTRC("UF"));
         if (csFileName.IsEmpty()) {
-            csFileName = CFX_WideString::FromLocal(pDict->GetString(FX_BSTRC("F")));
+            csFileName = CFX_WideString::FromLocal(pDict->GetStringAt("F"));
         }
-        if (pDict->GetString(FX_BSTRC("FS")) == FX_BSTRC("URL")) {
+        if (pDict->GetStringAt("FS") == "URL") {
             return TRUE;
         }
         if (csFileName.IsEmpty()) {
             if (pDict->KeyExist(FX_BSTRC("DOS"))) {
-                csFileName = CFX_WideString::FromLocal(pDict->GetString(FX_BSTRC("DOS")));
+                csFileName = CFX_WideString::FromLocal(
+                    pDict->GetStringAt("DOS"));
             } else if (pDict->KeyExist(FX_BSTRC("Mac"))) {
-                csFileName = CFX_WideString::FromLocal(pDict->GetString(FX_BSTRC("Mac")));
+                csFileName = CFX_WideString::FromLocal(
+                    pDict->GetStringAt("Mac"));
             } else if (pDict->KeyExist(FX_BSTRC("Unix"))) {
-                csFileName = CFX_WideString::FromLocal(pDict->GetString(FX_BSTRC("Unix")));
+                csFileName = CFX_WideString::FromLocal(
+                    pDict->GetStringAt("Unix"));
             } else {
                 return FALSE;
             }
@@ -360,7 +363,7 @@ FX_BOOL CPDF_FileSpec::IsURL() const
     if (m_pObj->GetType() != PDFOBJ_DICTIONARY) {
         return FALSE;
     }
-    return ((CPDF_Dictionary*)m_pObj)->GetString(FX_BSTRC("FS")) == FX_BSTRC("URL");
+    return ((CPDF_Dictionary*)m_pObj)->GetStringAt("FS") == "URL";
 }
 CFX_WideString FILESPEC_EncodeFileName(const CFX_WideStringC& filepath)
 {
@@ -530,7 +533,7 @@ CFX_WideString CPDF_PageLabel::GetLabel(int nPage) const
             if (pLabel->KeyExist(FX_BSTRC("P"))) {
                 wsLabel += pLabel->GetUnicodeText(FX_BSTRC("P"));
             }
-            CFX_ByteString bsNumberingStyle = pLabel->GetString(FX_BSTRC("S"), NULL);
+            CFX_ByteString bsNumberingStyle = pLabel->GetStringAt("S", NULL);
             int nLabelNum = nPage - n + pLabel->GetInteger(FX_BSTRC("St"), 1);
             CFX_WideString wsNumPortion = _GetLabelNumPortion(nLabelNum, bsNumberingStyle);
             wsLabel += wsNumPortion;