test/trace_processor/initial_display_state.textproto

packet: {
  timestamp: 1
  initial_display_state: {
    display_state: 2
    brightness: 0.5
  }
}
packet {
  ftrace_events {
    cpu: 0
    event {
      timestamp: 1000
      pid: 1234
      print {
        buf: "C|5678|ScreenState|0\n"
      }
    }
  }
}