Speedup rotation (#2468)

Speedup leader to validator transitions

benches/banking_stage.rs

@@ -101,6 +101,7 @@ fn bench_banking_stage_multi_accounts(bencher: &mut Bencher) {
             (x, iter::repeat(1).take(len).collect())
         })
         .collect();
+    let (to_leader_sender, _to_leader_recvr) = channel();
     let (_stage, signal_receiver) = BankingStage::new(
         &bank,
         verified_receiver,
@@ -108,6 +109,7 @@ fn bench_banking_stage_multi_accounts(bencher: &mut Bencher) {
         &genesis_block.last_id(),
         None,
         dummy_leader_id,
+        &to_leader_sender,
     );
 
     let mut id = genesis_block.last_id();
@@ -209,6 +211,7 @@ fn bench_banking_stage_multi_programs(bencher: &mut Bencher) {
             (x, iter::repeat(1).take(len).collect())
         })
         .collect();
+    let (to_leader_sender, _to_leader_recvr) = channel();
     let (_stage, signal_receiver) = BankingStage::new(
         &bank,
         verified_receiver,
@@ -216,6 +219,7 @@ fn bench_banking_stage_multi_programs(bencher: &mut Bencher) {
         &genesis_block.last_id(),
         None,
         dummy_leader_id,
+        &to_leader_sender,
     );
 
     let mut id = genesis_block.last_id();