Make CPDF_Object::GetString() a virtual method.

core/src/fpdfdoc/doc_utils.cpp

Index: core/src/fpdfdoc/doc_utils.cpp
diff --git a/core/src/fpdfdoc/doc_utils.cpp b/core/src/fpdfdoc/doc_utils.cpp
index 10ca14697d7ea46c4553ccaba7fe54cd678bffc1..858e0429f3b5524d74dc6a904bfec2bb030ffbf6 100644
--- a/core/src/fpdfdoc/doc_utils.cpp
+++ b/core/src/fpdfdoc/doc_utils.cpp
@@ -298,7 +298,7 @@ FX_DWORD CountInterFormFonts(CPDF_Dictionary* pFormDict)
         }
         CPDF_Object* pDirect = pObj->GetDirect();
         if (pDirect != NULL && pDirect->GetType() == PDFOBJ_DICTIONARY) {
-            if (((CPDF_Dictionary*)pDirect)->GetString("Type") == "Font") {
+            if (((CPDF_Dictionary*)pDirect)->GetStringAt("Type") == "Font") {
                 dwCount ++;
             }
         }
@@ -332,7 +332,7 @@ CPDF_Font* GetInterFormFont(CPDF_Dictionary* pFormDict, CPDF_Document* pDocument
             continue;
         }
         CPDF_Dictionary* pElement = (CPDF_Dictionary*)pDirect;
-        if (pElement->GetString("Type") != "Font") {
+        if (pElement->GetStringAt("Type") != "Font") {
             continue;
         }
         if (dwCount == index) {
@@ -361,7 +361,7 @@ CPDF_Font* GetInterFormFont(CPDF_Dictionary* pFormDict, CPDF_Document* pDocument
     if (pElement == NULL) {
         return NULL;
     }
-    if (pElement->GetString("Type") == "Font") {
+    if (pElement->GetStringAt("Type") == "Font") {
         return pDocument->LoadFont(pElement);
     }
     return NULL;
@@ -392,7 +392,7 @@ CPDF_Font* GetInterFormFont(CPDF_Dictionary* pFormDict, CPDF_Document* pDocument
             continue;
         }
         CPDF_Dictionary* pElement = (CPDF_Dictionary*)pDirect;
-        if (pElement->GetString("Type") != "Font") {
+        if (pElement->GetStringAt("Type") != "Font") {
             continue;
         }
         CPDF_Font* pFind = pDocument->LoadFont(pElement);
@@ -435,7 +435,7 @@ CPDF_Font* GetNativeInterFormFont(CPDF_Dictionary* pFormDict, CPDF_Document* pDo
             continue;
         }
         CPDF_Dictionary* pElement = (CPDF_Dictionary*)pDirect;
-        if (pElement->GetString("Type") != "Font") {
+        if (pElement->GetStringAt("Type") != "Font") {
             continue;
         }
         CPDF_Font* pFind = pDocument->LoadFont(pElement);
@@ -494,7 +494,7 @@ FX_BOOL FindInterFormFont(CPDF_Dictionary* pFormDict, const CPDF_Font* pFont, CF
             continue;
         }
         CPDF_Dictionary* pElement = (CPDF_Dictionary*)pDirect;
-        if (pElement->GetString("Type") != "Font") {
+        if (pElement->GetStringAt("Type") != "Font") {
             continue;
         }
         if (pFont->GetFontDict() == pElement) {
@@ -533,7 +533,7 @@ FX_BOOL FindInterFormFont(CPDF_Dictionary* pFormDict, CPDF_Document* pDocument,
             continue;
         }
         CPDF_Dictionary* pElement = (CPDF_Dictionary*)pDirect;
-        if (pElement->GetString("Type") != "Font") {
+        if (pElement->GetStringAt("Type") != "Font") {
             continue;
         }
         pFont = pDocument->LoadFont(pElement);
@@ -647,7 +647,7 @@ CPDF_Font* GetDefaultInterFormFont(CPDF_Dictionary* pFormDict, CPDF_Document* pD
     if (pFormDict == NULL) {
         return NULL;
     }
-    CPDF_DefaultAppearance cDA = pFormDict->GetString("DA");
+    CPDF_DefaultAppearance cDA = pFormDict->GetStringAt("DA");
     CFX_ByteString csFontNameTag;
     FX_FLOAT fFontSize;
     cDA.GetFont(csFontNameTag, fFontSize);
@@ -658,7 +658,7 @@ CPDF_IconFit::ScaleMethod CPDF_IconFit::GetScaleMethod()
     if (m_pDict == NULL) {
         return Always;
     }
-    CFX_ByteString csSW = m_pDict->GetString("SW", "A");
+    CFX_ByteString csSW = m_pDict->GetStringAt("SW", "A");
     if (csSW == "B") {
         return Bigger;
     } else if (csSW == "S") {
@@ -673,7 +673,7 @@ FX_BOOL CPDF_IconFit::IsProportionalScale()
     if (m_pDict == NULL) {
         return TRUE;
     }
-    return m_pDict->GetString("S", "P") != "A";
+    return m_pDict->GetStringAt("S", "P") != "A";
 }
 void CPDF_IconFit::GetIconPosition(FX_FLOAT& fLeft, FX_FLOAT& fBottom)
 {