txpool: don't maintain the pool during major sync (#13004)

* txpool: don't maintain the pool during major sync

Fix shall prevent from wasting the CPU during the major sync. No actions
are actually required in transaction pool during the major sync.

Fixes: #12903

* passing sync_oracle to maintain method

* fixed: builder, txpool tests

* do not maintain tx-pool if node gone out of sync

* EnactmentAction: all logic moved to EnactmentState

Tests to be done.

* maintain guard logic moved directly to MaintainedTransactionPool

* minor fixes

* EnactmentAction: all logic moved to EnactmentState (again)

* SyncOracle fixes here and there

* Update client/transaction-pool/src/enactment_state.rs

Co-authored-by: Bastian Köcher <git@kchr.de>

* Update client/transaction-pool/src/enactment_state.rs

Co-authored-by: Bastian Köcher <git@kchr.de>

* sync_oracle removed

* spelling + fmt + doc

* Review suggestions applied

* log::info -> debug

* Update client/transaction-pool/src/enactment_state.rs

Co-authored-by: Bastian Köcher <git@kchr.de>

* ".git/.scripts/commands/fmt/fmt.sh"

Co-authored-by: parity-processbot <>
Co-authored-by: Bastian Köcher <git@kchr.de>

substrate/Cargo.lock

@@ -9046,6 +9046,7 @@ dependencies = [
  "futures-timer",
  "linked-hash-map",
  "log",
+ "num-traits",
  "parity-scale-codec",
  "parking_lot 0.12.1",
  "sc-block-builder",