Merge "Avoid to call UI functions in child process"

    umask(022);

    close(pipefd[0]);

    execv(chr_args[0], const_cast<char**>(chr_args));

    PLOG(ERROR) << "Can't run " << chr_args[0];

    // Bug: 34769056

    // We shouldn't use LOG/PLOG in the forked process, since they may cause

    // the child process to hang. This deadlock results from an improperly

    // copied mutex in the ui functions.

    fprintf(stdout, "E:Can't run %s (%s)\n", chr_args[0], strerror(errno));

    _exit(-1);

  }

  close(pipefd[1]);