Standardize usage of virtual/override/final specifiers.

components/metrics/gpu/gpu_metrics_provider_unittest.cc

 // Copyright 2014 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 "components/metrics/gpu/gpu_metrics_provider.h"
 
 #include "base/basictypes.h"
 #include "components/metrics/proto/chrome_user_metrics_extension.pb.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/gfx/size.h"
@@ skipping 24 matching lines @@
   int GetScreenCount() const override { return kScreenCount; }
 
   DISALLOW_COPY_AND_ASSIGN(TestGPUMetricsProvider);
 };
 
 }  // namespace
 
 class GPUMetricsProviderTest : public testing::Test {
  public:
   GPUMetricsProviderTest() {}
-  virtual ~GPUMetricsProviderTest() {}
+  ~GPUMetricsProviderTest() override {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(GPUMetricsProviderTest);
 };
 
 TEST_F(GPUMetricsProviderTest, ProvideSystemProfileMetrics) {
   TestGPUMetricsProvider provider;
   ChromeUserMetricsExtension uma_proto;
 
   provider.ProvideSystemProfileMetrics(uma_proto.mutable_system_profile());
 
   // Check that the system profile has the correct values set.
   const SystemProfileProto::Hardware& hardware =
       uma_proto.system_profile().hardware();
   EXPECT_EQ(kScreenWidth, hardware.primary_screen_width());
   EXPECT_EQ(kScreenHeight, hardware.primary_screen_height());
   EXPECT_EQ(kScreenScaleFactor, hardware.primary_screen_scale_factor());
   EXPECT_EQ(kScreenCount, hardware.screen_count());
 }
 
 }  // namespace metrics