message: [tpu:profiler] Add a new field to the statistics collected at each step.
diff: @@ -87,6 +87,8 @@ message StepInfoResult {
  optional uint64 wait_duration_ps = 5;
  // The time spent on cross-replica-sum in picoseconds.
  optional uint64 crs_duration_ps = 6;
  + // Percentage of unit b time spent on infeed.
  + optional double unit_b_infeed_percent = 7;
  }
  // Result proto for a sequence of steps.
  