message: [XLA:CPU] Profile inside of conditionals
  Similar to while loops, not visiting them means we get a really coarse profile
  on a heavy conditional.
diff: @@ -254,6 +254,22 @@ class CollectProfileCandidates : public DfsHloVisitorWithDefault {
  TF_RETURN_IF_ERROR(call->to_apply()->Accept(&candidates_for_call));
  return Status::OK();
  }
  + // Recurse into "conditional" so we can profile inside of it.
  + Status HandleConditional(HloInstruction* conditional) override {
  + TF_RETURN_IF_ERROR(DefaultAction(conditional));
  +
  + CollectProfileCandidates candidates_for_true(hlo_to_profile_idx_,
  + assigned_indices_);
  + TF_RETURN_IF_ERROR(
  + conditional->true_computation()->Accept(&candidates_for_true));
  +
  + CollectProfileCandidates candidates_for_false(hlo_to_profile_idx_,
  + assigned_indices_);
  + TF_RETURN_IF_ERROR(
  + conditional->false_computation()->Accept(&candidates_for_false));
  +
  + return Status::OK();
  + }
  // Skip constants, there is nothing to profile.
  Status HandleConstant(HloInstruction*) override { return Status::OK(); }
  