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

ppapi/proxy/ppp_instance_private_proxy_unittest.cc

 // 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.
 
 #include "base/bind.h"
 #include "base/message_loop/message_loop.h"
 #include "base/test/test_timeouts.h"
 #include "base/time/time.h"
 #include "ppapi/c/dev/ppb_var_deprecated.h"
 #include "ppapi/c/dev/ppp_class_deprecated.h"
 #include "ppapi/c/pp_var.h"
 #include "ppapi/c/ppb_var.h"
 #include "ppapi/c/ppp_instance.h"
 #include "ppapi/c/private/ppp_instance_private.h"
 #include "ppapi/proxy/host_dispatcher.h"
 #include "ppapi/proxy/interface_list.h"
 #include "ppapi/proxy/ppapi_proxy_test.h"
 #include "ppapi/shared_impl/ppapi_permissions.h"
 #include "ppapi/shared_impl/ppb_var_shared.h"
 #include "ppapi/shared_impl/var.h"
 
 namespace ppapi {
 
 // A fake version of V8ObjectVar for testing.
 class V8ObjectVar : public ppapi::Var {
  public:
   V8ObjectVar() {}
-  virtual ~V8ObjectVar() {}
+  ~V8ObjectVar() override {}
 
   // Var overrides.
-  virtual V8ObjectVar* AsV8ObjectVar() override { return this; }
-  virtual PP_VarType GetType() const override { return PP_VARTYPE_OBJECT; }
+  V8ObjectVar* AsV8ObjectVar() override { return this; }
+  PP_VarType GetType() const override { return PP_VARTYPE_OBJECT; }
 };
 
 namespace proxy {
 
 namespace {
 const PP_Instance kInstance = 0xdeadbeef;
 
 PP_Var GetPPVarNoAddRef(Var* var) {
   PP_Var var_to_return = var->GetPPVar();
   PpapiGlobals::Get()->GetVarTracker()->ReleaseVar(var_to_return);
@@ skipping 158 matching lines @@
   // Destroy the instance. DidDestroy above decrements the reference count for
   // instance_obj, so it should also be destroyed.
   ppp_instance->DidDestroy(kInstance);
   EXPECT_EQ(-1, plugin().var_tracker().GetRefCountForObject(instance_obj));
   EXPECT_EQ(-1, host().var_tracker().GetRefCountForObject(host_pp_var));
 }
 
 }  // namespace proxy
 }  // namespace ppapi