Update {virtual,override} to follow C++11 style in ppapi.

ppapi/shared_impl/dictionary_var.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef PPAPI_SHARED_IMPL_DICTIONARY_VAR_H_
 #define PPAPI_SHARED_IMPL_DICTIONARY_VAR_H_
 
 #include <map>
 #include <string>
 
@@ skipping 11 matching lines @@
   typedef std::map<std::string, ScopedPPVar> KeyValueMap;
 
   DictionaryVar();
 
   // Helper function that converts a PP_Var to a DictionaryVar. This will
   // return NULL if the PP_Var is not of type PP_VARTYPE_DICTIONARY or the
   // dictionary cannot be found from the var tracker.
   static DictionaryVar* FromPPVar(const PP_Var& var);
 
   // Var overrides.
-  virtual DictionaryVar* AsDictionaryVar() override;
-  virtual PP_VarType GetType() const override;
+  DictionaryVar* AsDictionaryVar() override;
+  PP_VarType GetType() const override;
 
   // The returned PP_Var has had a ref added on behalf of the caller.
   PP_Var Get(const PP_Var& key) const;
   PP_Bool Set(const PP_Var& key, const PP_Var& value);
   void Delete(const PP_Var& key);
   PP_Bool HasKey(const PP_Var& key) const;
   // The returned PP_Var has had a ref added on behalf of the caller.
   PP_Var GetKeys() const;
 
   // Returns false and keeps the dictionary unchanged if |key| is not a valid
   // UTF-8 string.
   bool SetWithStringKey(const std::string& utf8_key, const PP_Var& value);
   void DeleteWithStringKey(const std::string& utf8_key);
 
   const KeyValueMap& key_value_map() const { return key_value_map_; }
 
  protected:
-  virtual ~DictionaryVar();
+  ~DictionaryVar() override;
 
  private:
   KeyValueMap key_value_map_;
 
   DISALLOW_COPY_AND_ASSIGN(DictionaryVar);
 };
 
 }  // namespace ppapi
 
 #endif  // PPAPI_SHARED_IMPL_DICTIONARY_VAR_H_