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

ppapi/shared_impl/var.h

 // Copyright (c) 2012 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_VAR_H_
 #define PPAPI_SHARED_IMPL_VAR_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
@@ skipping 83 matching lines @@
 //
 // Converting a PP_Var to a string:
 //   StringVar* string = StringVar::FromPPVar(var);
 //   if (!string)
 //     return false;  // Not a string or an invalid var.
 //   DoSomethingWithTheString(string->value());
 class PPAPI_SHARED_EXPORT StringVar : public Var {
  public:
   explicit StringVar(const std::string& str);
   StringVar(const char* str, uint32 len);
-  virtual ~StringVar();
+  ~StringVar() override;
 
   const std::string& value() const { return value_; }
   // Return a pointer to the internal string. This allows other objects to
   // temporarily store a weak pointer to our internal string. Use with care; the
   // pointer *will* become invalid if this StringVar is removed from the
   // tracker. (All of this applies to value(), but this one's even easier to use
   // dangerously).
   const std::string* ptr() const { return &value_; }
 
   // Var override.
-  virtual StringVar* AsStringVar() override;
-  virtual PP_VarType GetType() const override;
+  StringVar* AsStringVar() override;
+  PP_VarType GetType() const override;
 
   // Helper function to create a PP_Var of type string that contains a copy of
   // the given string. The input data must be valid UTF-8 encoded text, if it
   // is not valid UTF-8, a NULL var will be returned.
   //
   // The return value will have a reference count of 1. Internally, this will
   // create a StringVar and return the reference to it in the var.
   static PP_Var StringToPPVar(const std::string& str);
   static PP_Var StringToPPVar(const char* str, uint32 len);
 
@@ skipping 24 matching lines @@
 //       PpapiGlobals::Get()->GetVarTracker()->CreateArrayBuffer(size);
 //
 // Converting a PP_Var to an ArrayBufferVar:
 //   ArrayBufferVar* array = ArrayBufferVar::FromPPVar(var);
 //   if (!array)
 //     return false;  // Not an ArrayBuffer or an invalid var.
 //   DoSomethingWithTheBuffer(array);
 class PPAPI_SHARED_EXPORT ArrayBufferVar : public Var {
  public:
   ArrayBufferVar();
-  virtual ~ArrayBufferVar();
+  ~ArrayBufferVar() override;
 
   virtual void* Map() = 0;
   virtual void Unmap() = 0;
   virtual uint32 ByteLength() = 0;
 
   // Creates a new shared memory region, and copies the data in the
   // ArrayBufferVar into it. On the plugin side, host_shm_handle_id will be set
   // to some value that is not -1. On the host side, plugin_shm_handle will be
   // set to a valid SharedMemoryHandle.
   //
   // Returns true if creating the shared memory (and copying) is successful,
   // false otherwise.
   virtual bool CopyToNewShmem(PP_Instance instance,
                               int* host_shm_handle_id,
                               base::SharedMemoryHandle* plugin_shm_handle) = 0;
 
   // Var override.
-  virtual ArrayBufferVar* AsArrayBufferVar() override;
-  virtual PP_VarType GetType() const override;
+  ArrayBufferVar* AsArrayBufferVar() override;
+  PP_VarType GetType() const override;
 
   // Helper function that converts a PP_Var to an ArrayBufferVar. This will
   // return NULL if the PP_Var is not of ArrayBuffer type.
   static ArrayBufferVar* FromPPVar(PP_Var var);
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ArrayBufferVar);
 };
 
 }  // namespace ppapi
 
 #endif  // PPAPI_SHARED_IMPL_VAR_H_