Standardize usage of virtual/override/final in ipc/

ipc/unix_domain_socket_util_unittest.cc

Index: ipc/unix_domain_socket_util_unittest.cc
diff --git a/ipc/unix_domain_socket_util_unittest.cc b/ipc/unix_domain_socket_util_unittest.cc
index a67c0773026b6cd2ced554ec879e291ebc353f92..90c2ada7540274b3a9cd6b5a9a9b85f235b248a8 100644
--- a/ipc/unix_domain_socket_util_unittest.cc
+++ b/ipc/unix_domain_socket_util_unittest.cc
@@ -27,9 +27,7 @@ class SocketAcceptor : public base::MessageLoopForIO::Watcher {
         base::Bind(&SocketAcceptor::StartWatching, base::Unretained(this), fd));
   }
 
-  virtual ~SocketAcceptor() {
-    Close();
-  }
+  ~SocketAcceptor() override { Close(); }
 
   int server_fd() const { return server_fd_; }
 
@@ -60,13 +58,13 @@ class SocketAcceptor : public base::MessageLoopForIO::Watcher {
     watcher->StopWatchingFileDescriptor();
     delete watcher;
   }
-  virtual void OnFileCanReadWithoutBlocking(int fd) override {
+  void OnFileCanReadWithoutBlocking(int fd) override {
     ASSERT_EQ(-1, server_fd_);
     IPC::ServerAcceptConnection(fd, &server_fd_);
     watcher_->StopWatchingFileDescriptor();
     accepted_event_.Signal();
   }
-  virtual void OnFileCanWriteWithoutBlocking(int fd) override {}
+  void OnFileCanWriteWithoutBlocking(int fd) override {}
 
   int server_fd_;
   base::MessageLoopProxy* target_thread_;