Standardize usage of virtual/override/final specifiers.

content/renderer/media/webrtc/video_destination_handler_unittest.cc

 // Copyright (c) 2013 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 <string>
 
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/child/child_process.h"
@@ skipping 23 matching lines @@
 static const std::string kUnknownStreamUrl = "unknown_stream_url";
 
 class VideoDestinationHandlerTest : public PpapiUnittest {
  public:
   VideoDestinationHandlerTest()
      : child_process_(new ChildProcess()),
        registry_(new MockMediaStreamRegistry()) {
     registry_->Init(kTestStreamUrl);
   }
 
-  virtual void TearDown() override {
+  void TearDown() override {
     registry_.reset();
     blink::WebHeap::collectAllGarbageForTesting();
     PpapiUnittest::TearDown();
   }
 
   base::MessageLoop* io_message_loop() const {
     return child_process_->io_message_loop();
   }
 
  protected:
@@ skipping 52 matching lines @@
     base::MessageLoop::current()->RunUntilIdle();
   }
   EXPECT_EQ(1, sink.number_of_frames());
   native_track->RemoveSink(&sink);
 
   // The |frame_writer| is a proxy and is owned by whoever call Open.
   delete frame_writer;
 }
 
 }  // namespace content