Prepare for asynchronous transaction validation in tx pool (#3650)

* async txpool API

* Update core/rpc/src/author/mod.rs

Co-Authored-By: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Update core/transaction-pool/graph/src/pool.rs

Co-Authored-By: Tomasz Drwięga <tomusdrw@users.noreply.github.com>

* Pool -> Pool + ValidatedPool

* removed lost block_on when importing xt from network

* fix grumbles

* alias for future::Executor in rpc

* removed executor from Author RPCs

* Pool + SharedValidatedPool -> Pool

* fix compilation after merge

* another fix

* another fix

substrate/core/network/src/service.rs

@@ -65,8 +65,18 @@ impl<T> ExHashT for T where
 pub trait TransactionPool<H: ExHashT, B: BlockT>: Send + Sync {
 	/// Get transactions from the pool that are ready to be propagated.
 	fn transactions(&self) -> Vec<(H, B::Extrinsic)>;
+	/// Get hash of transaction.
+	fn hash_of(&self, transaction: &B::Extrinsic) -> H;
 	/// Import a transaction into the pool.
-	fn import(&self, transaction: &B::Extrinsic) -> Option<H>;
+	///
+	/// Peer reputation is changed by reputation_change if transaction is accepted by the pool.
+	fn import(
+		&self,
+		report_handle: ReportHandle,
+		who: PeerId,
+		reputation_change: i32,
+		transaction: B::Extrinsic,
+	);
 	/// Notify the pool about transactions broadcast.
 	fn on_broadcasted(&self, propagations: HashMap<H, Vec<String>>);
 }
@@ -77,6 +87,12 @@ pub struct ReportHandle {
 	inner: PeersetHandle, // wraps it so we don't have to worry about breaking API.
 }
 
+impl From<PeersetHandle> for ReportHandle {
+	fn from(peerset_handle: PeersetHandle) -> Self {
+		ReportHandle { inner: peerset_handle }
+	}
+}
+
 impl ReportHandle {
 	/// Report a given peer as either beneficial (+) or costly (-) according to the
 	/// given scalar.