Standardize usage of virtual/override/final specifiers.

gpu/command_buffer/common/debug_marker_manager_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 "gpu/command_buffer/common/debug_marker_manager.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/gl/gl_mock.h"
 
 namespace gpu {
 namespace gles2 {
 
 class DebugMarkerManagerTest : public testing::Test {
  protected:
-  virtual void SetUp() {
-  }
+  void SetUp() override {}
 
-  virtual void TearDown() {
-  }
+  void TearDown() override {}
 
   DebugMarkerManager manager_;
 };
 
 TEST_F(DebugMarkerManagerTest, Basic) {
   // Test we can get root
   EXPECT_STREQ("", manager_.GetMarker().c_str());
   // Test it's safe to pop an empty stack.
   manager_.PopGroup();
   // Test we can still get root.
@@ skipping 25 matching lines @@
   manager_.PopGroup();
   EXPECT_STREQ(".mark2", manager_.GetMarker().c_str());
   manager_.PopGroup();
   EXPECT_STREQ(".mark2", manager_.GetMarker().c_str());
 }
 
 }  // namespace gles2
 }  // namespace gpu