kvserver/batcheval: remove unused arg

This arg used to determine whether reads need to block on lease
transfers, but that stopped being the case in ed9c68a.

Release note: None

pkg/kv/kvserver/batcheval/cmd_lease.go

@@ -41,10 +41,6 @@ func newFailedLeaseTrigger(isTransfer bool) result.Result {
 // The new lease might be a lease for a range that didn't previously have an
 // active lease, might be an extension or a lease transfer.
 //
-// isExtension should be set if the lease holder does not change with this
-// lease. If it doesn't change, we don't need the application of this lease to
-// block reads.
-//
 // TODO(tschottdorf): refactoring what's returned from the trigger here makes
 // sense to minimize the amount of code intolerant of rolling updates.
 func evalNewLease(
@@ -55,7 +51,6 @@ func evalNewLease(
 	lease roachpb.Lease,
 	prevLease roachpb.Lease,
 	priorReadSum *rspb.ReadSummary,
-	isExtension bool,
 	isTransfer bool,
 ) (result.Result, error) {
 	// When returning an error from this method, must always return

pkg/kv/kvserver/batcheval/cmd_lease_request.go

@@ -158,5 +158,5 @@ func RequestLease(
 	}
 
 	return evalNewLease(ctx, cArgs.EvalCtx, readWriter, cArgs.Stats,
-		newLease, prevLease, priorReadSum, isExtension, false /* isTransfer */)
+		newLease, prevLease, priorReadSum, false /* isTransfer */)
 }

pkg/kv/kvserver/batcheval/cmd_lease_transfer.go

@@ -130,5 +130,5 @@ func TransferLease(
 
 	log.VEventf(ctx, 2, "lease transfer: prev lease: %+v, new lease: %+v", prevLease, newLease)
 	return evalNewLease(ctx, cArgs.EvalCtx, readWriter, cArgs.Stats,
-		newLease, prevLease, &priorReadSum, false /* isExtension */, true /* isTransfer */)
+		newLease, prevLease, &priorReadSum, true /* isTransfer */)
 }