Standardize usage of virtual/override/final in printing/

printing/metafile.h

Index: printing/metafile.h
diff --git a/printing/metafile.h b/printing/metafile.h
index 0078d8b1f7d081dea2c6b4199a26da2535f87f9f..12b50334e432cb9c6b158f14b58bb3dfb9577f71 100644
--- a/printing/metafile.h
+++ b/printing/metafile.h
@@ -99,7 +99,7 @@ class PRINTING_EXPORT MetafilePlayer {
 class PRINTING_EXPORT Metafile : public MetafilePlayer {
  public:
   Metafile();
-  virtual ~Metafile();
+  ~Metafile() override;
 
   // Initializes a fresh new metafile for rendering. Returns false on failure.
   // Note: It should only be called from within the renderer process to allocate
@@ -163,7 +163,7 @@ class PRINTING_EXPORT Metafile : public MetafilePlayer {
 
   bool GetDataAsVector(std::vector<char>* buffer) const;
 
-  virtual bool SaveTo(base::File* file) const override;
+  bool SaveTo(base::File* file) const override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(Metafile);