Implement FPDF_VIEWERREF_GetName() API.

core/fpdfdoc/cpdf_viewerpreferences.cpp

Index: core/fpdfdoc/cpdf_viewerpreferences.cpp
diff --git a/core/fpdfdoc/cpdf_viewerpreferences.cpp b/core/fpdfdoc/cpdf_viewerpreferences.cpp
index 799f2d58144d1ffc6e23842233f64b52f01d60aa..a31ba49ac33f3c476e7cf04cbc674c7dcd577b76 100644
--- a/core/fpdfdoc/cpdf_viewerpreferences.cpp
+++ b/core/fpdfdoc/cpdf_viewerpreferences.cpp
@@ -7,6 +7,7 @@
 #include "core/fpdfdoc/cpdf_viewerpreferences.h"
 
 #include "core/fpdfapi/parser/cpdf_document.h"
+#include "core/fpdfapi/parser/cpdf_name.h"
 
 CPDF_ViewerPreferences::CPDF_ViewerPreferences(CPDF_Document* pDoc)
     : m_pDoc(pDoc) {}
@@ -38,6 +39,20 @@ CFX_ByteString CPDF_ViewerPreferences::Duplex() const {
   return pDict ? pDict->GetStringFor("Duplex") : CFX_ByteString("None");
 }
 
+bool CPDF_ViewerPreferences::GenericName(const CFX_ByteString& bsKey,
+                                         CFX_ByteString* bsVal) const {
+  CPDF_Dictionary* pDict = GetViewerPreferences();
+  if (!pDict)
+    return false;
+
+  const CPDF_Name* pName = ToName(pDict->GetObjectFor(bsKey));
+  if (!pName)
+    return false;
+
+  *bsVal = pName->GetString();
+  return true;
+}
+
 CPDF_Dictionary* CPDF_ViewerPreferences::GetViewerPreferences() const {
   CPDF_Dictionary* pDict = m_pDoc->GetRoot();
   return pDict ? pDict->GetDictFor("ViewerPreferences") : nullptr;