test/trace_processor/power/power_rails.textproto

packet {
  power_rails {
    rail_descriptor {
      index: 4
      rail_name: "test_rail"
      subsys_name: "test_subsys"
      sampling_rate: 1023
    }
  }
}
packet {
  timestamp: 3000003
  power_rails {
    energy_data {
      index: 4
      timestamp_ms: 3
      energy: 333
    }
  }
}
packet {
  timestamp: 3000005
  power_rails {
    rail_descriptor {
      index: 3
      rail_name: "test_rail2"
      subsys_name: "test_subsys2"
      sampling_rate: 1022
    }
    energy_data {
      index: 4
      timestamp_ms: 5
      energy: 666
    }
    energy_data {
      index: 3
      energy: 999
    }
    energy_data {
      index: 4
      timestamp_ms: 3
      energy: 0
    }
  }
}

packet {
  ftrace_events {
    cpu: 2
    event {
      timestamp: 3000004
      pid: 1257
      print {
        buf: "C|1204|Testing|1000\n"
      }
    }
  }
}