message: Add more data fields to step proto.
diff: @@ -79,12 +79,15 @@ message StepInfoResult {
  // The step duration in picoseconds.
  optional uint64 duration_ps = 2;
  // The infeed duration in picoseconds.
  - // Can turn into a map if we want a variable number of ops.
  optional uint64 infeed_duration_ps = 3;
  + // The outfeed duration in picoseconds.
  + optional uint64 host_outfeed_ps = 8;
  // The start time of this step in picoseconds.
  optional uint64 begin_ps = 4;
  // The waiting time within this step in picoseconds.
  optional uint64 wait_duration_ps = 5;
  + // The unit b outfeed duration in picoseconds.
  + optional uint64 unit_b_outfeed_ps = 9;
  // The time spent on cross-replica-sum in picoseconds.
  optional uint64 crs_duration_ps = 6;
  // Percentage of unit b time spent on infeed.
  