Upgradeable validation functions (#918)

* upgrade primitives to allow changing validation function

* set up storage schema for old parachains code

* fix compilation errors

* fix test compilation

* add some tests for past code meta

* most of the runtime logic for code upgrades

* implement old-code pruning

* add a couple tests

* clean up remaining TODOs

* add a whole bunch of tests for runtime functionality

* remove unused function

* fix runtime compilation

* extract some primitives to parachain crate

* add validation-code upgrades to validation params and result

* extend validation params with code upgrade fields

* provide maximums to validation params

* port test-parachains

* add a code-upgrader test-parachain and tests

* fix collator tests

* move test-parachains to own folder to work around compilation errors

* fix test compilation

* update the Cargo.lock

* fix parachains tests

* remove dbg! invocation

* use new pool in code-upgrader

* bump lockfile

* link TODO to issue

polkadot/collator/src/lib.rs

@@ -59,7 +59,7 @@ use polkadot_primitives::{
 	BlockId, Hash, Block,
 	parachain::{
 		self, BlockData, DutyRoster, HeadData, Id as ParaId,
-		PoVBlock, ValidatorId, CollatorPair, LocalValidationData
+		PoVBlock, ValidatorId, CollatorPair, LocalValidationData, GlobalValidationSchedule,
 	}
 };
 use polkadot_cli::{
@@ -154,7 +154,8 @@ pub trait ParachainContext: Clone {
 	fn produce_candidate(
 		&mut self,
 		relay_parent: Hash,
-		status: LocalValidationData,
+		global_validation: GlobalValidationSchedule,
+		local_validation: LocalValidationData,
 	) -> Self::ProduceCandidate;
 }
 
@@ -162,6 +163,7 @@ pub trait ParachainContext: Clone {
 pub async fn collate<P>(
 	relay_parent: Hash,
 	local_id: ParaId,
+	global_validation: GlobalValidationSchedule,
 	local_validation_data: LocalValidationData,
 	mut para_context: P,
 	key: Arc<CollatorPair>,
@@ -173,6 +175,7 @@ pub async fn collate<P>(
 {
 	let (block_data, head_data) = para_context.produce_candidate(
 		relay_parent,
+		global_validation,
 		local_validation_data,
 	).map_err(Error::Collator).await?;
 
@@ -281,6 +284,7 @@ fn build_collator_service<S, P, Extrinsic>(
 
 			let work = future::lazy(move |_| {
 				let api = client.runtime_api();
+				let global_validation = try_fr!(api.global_validation_schedule(&id));
 				let local_validation = match try_fr!(api.local_validation_data(&id, para_id)) {
 					Some(local_validation) => local_validation,
 					None => return future::Either::Left(future::ok(())),
@@ -297,6 +301,7 @@ fn build_collator_service<S, P, Extrinsic>(
 				let collation_work = collate(
 					relay_parent,
 					para_id,
+					global_validation,
 					local_validation,
 					parachain_context,
 					key,
@@ -427,6 +432,7 @@ mod tests {
 		fn produce_candidate(
 			&mut self,
 			_relay_parent: Hash,
+			_global: GlobalValidationSchedule,
 			_local_validation: LocalValidationData,
 		) -> Self::ProduceCandidate {
 			// send messages right back.