[Android] Fix gn build for instrumentation tests.

tools/android/forwarder2/daemon.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 "tools/android/forwarder2/daemon.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <signal.h>
 #include <sys/file.h>
@@ skipping 80 matching lines @@
   string_builder.Append("Daemon (pid=%d) died unexpectedly with ", child_pid);
   if (WIFEXITED(status))
     string_builder.Append("status %d.", WEXITSTATUS(status));
   else if (WIFSIGNALED(status))
     string_builder.Append("signal %d.", WTERMSIG(status));
   else
     string_builder.Append("unknown reason.");
   SIGNAL_SAFE_LOG(ERROR, string_builder.buffer());
 }
 
-// Note that 0 is written to |lock_owner_pid| in case the file is not locked.
-bool GetFileLockOwnerPid(int fd, pid_t* lock_owner_pid) {
-  struct flock lock_info = {};
-  lock_info.l_type = F_WRLCK;
-  lock_info.l_whence = SEEK_CUR;
-  const int ret = HANDLE_EINTR(fcntl(fd, F_GETLK, &lock_info));
-  if (ret < 0) {
-    if (errno == EBADF) {
-      // Assume that the provided file descriptor corresponding to the PID file
-      // was valid until the daemon removed this file.
-      *lock_owner_pid = 0;
-      return true;
-    }
-    PError("fcntl");
-    return false;
-  }
-  if (lock_info.l_type == F_UNLCK) {
-    *lock_owner_pid = 0;
-    return true;
-  }
-  CHECK_EQ(F_WRLCK /* exclusive lock */, lock_info.l_type);
-  *lock_owner_pid = lock_info.l_pid;
-  return true;
-}
-
 scoped_ptr<Socket> ConnectToUnixDomainSocket(
     const std::string& socket_name,
     int tries_count,
     int idle_time_msec,
     const std::string& expected_welcome_message) {
   for (int i = 0; i < tries_count; ++i) {
     scoped_ptr<Socket> socket(new Socket());
     if (!socket->ConnectUnix(socket_name)) {
       if (idle_time_msec)
         usleep(idle_time_msec * 1000);
@@ skipping 145 matching lines @@
       return true;
     }
     usleep(kIdleTimeMSec * 1000);
   }
   LOG(ERROR) << "Timed out while killing daemon. "
                 "It might still be tearing down.";
   return false;
 }
 
 }  // namespace forwarder2