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

ppapi/shared_impl/var_tracker_unittest.cc

 // Copyright (c) 2011 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 "testing/gtest/include/gtest/gtest.h"
 
 #include "base/compiler_specific.h"
 #include "ppapi/shared_impl/proxy_lock.h"
 #include "ppapi/shared_impl/var.h"
 #include "ppapi/shared_impl/var_tracker.h"
 #include "ppapi/shared_impl/test_globals.h"
 
 namespace ppapi {
 
 namespace {
 
 int mock_var_alive_count = 0;
 
 class MockStringVar : public StringVar {
  public:
   MockStringVar(const std::string& str) : StringVar(str) {
     mock_var_alive_count++;
   }
-  virtual ~MockStringVar() { mock_var_alive_count--; }
+  ~MockStringVar() override { mock_var_alive_count--; }
   bool HasValidVarID() { return GetExistingVarID() != 0; }
 };
 
 class MockObjectVar : public Var {
  public:
   MockObjectVar() : Var() { mock_var_alive_count++; }
-  virtual ~MockObjectVar() { mock_var_alive_count--; }
-  virtual PP_VarType GetType() const override { return PP_VARTYPE_OBJECT; }
+  ~MockObjectVar() override { mock_var_alive_count--; }
+  PP_VarType GetType() const override { return PP_VARTYPE_OBJECT; }
   bool HasValidVarID() { return GetExistingVarID() != 0; }
 };
 
 }  // namespace
 
 class VarTrackerTest : public testing::Test {
  public:
   VarTrackerTest() {}
 
   // Test implementation.
-  virtual void SetUp() override {
+  void SetUp() override {
     ASSERT_EQ(0, mock_var_alive_count);
   }
-  virtual void TearDown() override {}
+  void TearDown() override {}
 
   VarTracker& var_tracker() { return *globals_.GetVarTracker(); }
 
  private:
   TestGlobals globals_;
 };
 
 // Test that ResetVarID is called when the last PP_Var ref was deleted but the
 // object lives on.
 TEST_F(VarTrackerTest, LastResourceRef) {
@@ skipping 85 matching lines @@
   another_var = NULL;
   EXPECT_TRUE(var_tracker().GetVar(pp_var));
   EXPECT_EQ(1, mock_var_alive_count);
 
   // Releasing plugin reference.
   EXPECT_TRUE(var_tracker().ReleaseVar(pp_var));
   EXPECT_EQ(0, mock_var_alive_count);
 }
 
 }  // namespace ppapi