Make CPDF_Object::GetString() a virtual method.

core/src/fpdfdoc/doc_tagged.cpp

Index: core/src/fpdfdoc/doc_tagged.cpp
diff --git a/core/src/fpdfdoc/doc_tagged.cpp b/core/src/fpdfdoc/doc_tagged.cpp
index e9f0c55e2ba067988e2c76cfc085dd7c9e968456..909d17ca2b2d73b1165538c20de181d508b8d70b 100644
--- a/core/src/fpdfdoc/doc_tagged.cpp
+++ b/core/src/fpdfdoc/doc_tagged.cpp
@@ -131,7 +131,7 @@ CPDF_StructElementImpl* CPDF_StructTreeImpl::AddPageNode(CPDF_Dictionary* pDict,
     pElement = new CPDF_StructElementImpl(this, NULL, pDict);
     map.SetAt(pDict, pElement);
     CPDF_Dictionary* pParent = pDict->GetDict(FX_BSTRC("P"));
-    if (pParent == NULL || pParent->GetString(FX_BSTRC("Type")) == FX_BSTRC("StructTreeRoot")) {
+    if (pParent == NULL || pParent->GetStringAt("Type") == "StructTreeRoot") {
         if (!AddTopLevelNode(pDict, pElement)) {
             pElement->Release();
             map.RemoveKey(pDict);
@@ -201,9 +201,9 @@ CPDF_StructElementImpl::CPDF_StructElementImpl(CPDF_StructTreeImpl* pTree, CPDF_
 {
     m_pTree = pTree;
     m_pDict = pDict;
-    m_Type = pDict->GetString(FX_BSTRC("S"));
+    m_Type = pDict->GetStringAt("S");
     if (pTree->m_pRoleMap) {
-        CFX_ByteString mapped = pTree->m_pRoleMap->GetString(m_Type);
+        CFX_ByteString mapped = pTree->m_pRoleMap->GetStringAt(m_Type);
         if (!mapped.IsEmpty()) {
             m_Type = mapped;
         }
@@ -276,7 +276,7 @@ void CPDF_StructElementImpl::LoadKid(FX_DWORD PageObjNum, CPDF_Object* pKidObj,
     if (pPageObj && pPageObj->GetType() == PDFOBJ_REFERENCE) {
         PageObjNum = ((CPDF_Reference*)pPageObj)->GetRefObjNum();
     }
-    CFX_ByteString type = pKidDict->GetString(FX_BSTRC("Type"));
+    CFX_ByteString type = pKidDict->GetStringAt("Type");
     if (type == FX_BSTRC("MCR")) {
         if (m_pTree->m_pPage && m_pTree->m_pPage->GetObjNum() != PageObjNum) {
             return;
@@ -335,7 +335,7 @@ static CPDF_Dictionary* FindAttrDict(CPDF_Object* pAttrs, const CFX_ByteStringC&
             }
         }
     }
-    if (pDict && pDict->GetString(FX_BSTRC("O")) == owner) {
+    if (pDict && pDict->GetStringAt("O") == owner) {
         return pDict;
     }
     return NULL;
@@ -376,9 +376,9 @@ CPDF_Object* CPDF_StructElementImpl::GetAttr(const CFX_ByteStringC& owner, const
     if (pC->GetType() == PDFOBJ_ARRAY) {
         CPDF_Array* pArray = (CPDF_Array*)pC;
         for (FX_DWORD i = 0; i < pArray->GetCount(); i ++) {
-            CFX_ByteString class_name = pArray->GetString(i);
+            CFX_ByteString class_name = pArray->GetStringAt(i);
             CPDF_Dictionary* pClassDict = pClassMap->GetDict(class_name);
-            if (pClassDict && pClassDict->GetString(FX_BSTRC("O")) == owner) {
+            if (pClassDict && pClassDict->GetStringAt("O") == owner) {
                 return pClassDict->GetElementValue(name);
             }
         }
@@ -386,7 +386,7 @@ CPDF_Object* CPDF_StructElementImpl::GetAttr(const CFX_ByteStringC& owner, const
     }
     CFX_ByteString class_name = pC->GetString();
     CPDF_Dictionary* pClassDict = pClassMap->GetDict(class_name);
-    if (pClassDict && pClassDict->GetString(FX_BSTRC("O")) == owner) {
+    if (pClassDict && pClassDict->GetStringAt("O") == owner) {
         return pClassDict->GetElementValue(name);
     }
     return NULL;