Remove dead code from CPDF_Metadata. Add missing nullptr check.

core/include/fpdfdoc/fpdf_doc.h

 // 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
 
 #ifndef CORE_INCLUDE_FPDFDOC_FPDF_DOC_H_
 #define CORE_INCLUDE_FPDFDOC_FPDF_DOC_H_
 
 #include <map>
 
+#include "../../../third_party/base/nonstd_unique_ptr.h"
 #include "../fpdfapi/fpdf_parser.h"
 #include "../fpdfapi/fpdf_render.h"
 
 class CFieldTree;
 class CPDF_AAction;
 class CPDF_Action;
 class CPDF_ActionFields;
 class CPDF_Annot;
 class CPDF_AnnotList;
 class CPDF_ApSettings;
@@ skipping 1122 matching lines @@
 
   CFX_WideString GetLabel(int nPage) const;
 
   int32_t GetPageByLabel(const CFX_ByteStringC& bsLabel) const;
 
   int32_t GetPageByLabel(const CFX_WideStringC& wsLabel) const;
 
  protected:
   CPDF_Document* m_pDocument;
 };
+
 class CPDF_Metadata {
  public:
-  CPDF_Metadata();
-
+  explicit CPDF_Metadata(CPDF_Document* pDoc);
   ~CPDF_Metadata();
 
-  void LoadDoc(CPDF_Document* pDoc);
+  const CXML_Element* GetRoot() const;
 
-  int32_t GetString(const CFX_ByteStringC& bsItem, CFX_WideString& wsStr);
+ private:
+  CPDF_Document* const m_pDoc;  // Not owned.
+  nonstd::unique_ptr<CXML_Element> m_pXmlElement;
+};
 
-  CXML_Element* GetRoot() const;
-
-  CXML_Element* GetRDF() const;
-
- protected:
-  void* m_pData;
-};
 class CPDF_ViewerPreferences {
  public:
   CPDF_ViewerPreferences(CPDF_Document* pDoc);
 
   ~CPDF_ViewerPreferences();
 
   FX_BOOL IsDirectionR2L() const;
 
   FX_BOOL PrintScaling() const;
 
@@ skipping 71 matching lines @@
                         FX_FLOAT fc[4],
                         const CFX_ByteStringC& csEntry);
 
   CFX_WideString GetCaption(const CFX_ByteStringC& csEntry);
 
   CPDF_Stream* GetIcon(const CFX_ByteStringC& csEntry);
   friend class CPDF_FormControl;
 };
 
 #endif  // CORE_INCLUDE_FPDFDOC_FPDF_DOC_H_