Remove AssignmentProviderConfig and use parameters from HostConfiguration instead (#3181)

This PR removes `AssignmentProviderConfig` and uses the corresponding
ondemand parameters from `HostConfiguration` instead. Additionally
`scheduling_lookahead` and all coretime/ondemand related parameters are
extracted in a separate struct - `SchedulerParams`.

The most relevant commit from the PR is [this
one](https://github.com/paritytech/polkadot-sdk/pull/3181/commits/830bc0f5e858944474171bbe33382ad96040b535).

Fixes https://github.com/paritytech/polkadot-sdk/issues/2268

---------

Co-authored-by: command-bot <>

polkadot/node/service/src/chain_spec.rs

@@ -24,6 +24,8 @@ use polkadot_primitives::{AccountId, AccountPublic, AssignmentId, ValidatorId};
 use sp_authority_discovery::AuthorityId as AuthorityDiscoveryId;
 use sp_consensus_babe::AuthorityId as BabeId;
 
+#[cfg(any(feature = "rococo-native", feature = "westend-native",))]
+use polkadot_primitives::vstaging::SchedulerParams;
 #[cfg(feature = "rococo-native")]
 use rococo_runtime as rococo;
 #[cfg(feature = "rococo-native")]
@@ -129,8 +131,6 @@ fn default_parachains_host_configuration(
 		max_code_size: MAX_CODE_SIZE,
 		max_pov_size: MAX_POV_SIZE,
 		max_head_data_size: 32 * 1024,
-		group_rotation_frequency: 20,
-		paras_availability_period: 4,
 		max_upward_queue_count: 8,
 		max_upward_queue_size: 1024 * 1024,
 		max_downward_message_size: 1024 * 1024,
@@ -151,11 +151,16 @@ fn default_parachains_host_configuration(
 		relay_vrf_modulo_samples: 2,
 		zeroth_delay_tranche_width: 0,
 		minimum_validation_upgrade_delay: 5,
-		scheduling_lookahead: 2,
 		async_backing_params: AsyncBackingParams {
 			max_candidate_depth: 3,
 			allowed_ancestry_len: 2,
 		},
+		scheduler_params: SchedulerParams {
+			lookahead: 2,
+			group_rotation_frequency: 20,
+			paras_availability_period: 4,
+			..Default::default()
+		},
 		..Default::default()
 	}
 }
@@ -891,7 +896,10 @@ pub fn rococo_testnet_genesis(
 		"sudo": { "key": Some(root_key.clone()) },
 		"configuration": {
 			"config": polkadot_runtime_parachains::configuration::HostConfiguration {
-				max_validators_per_core: Some(1),
+				scheduler_params: SchedulerParams {
+					max_validators_per_core: Some(1),
+					..default_parachains_host_configuration().scheduler_params
+				},
 				..default_parachains_host_configuration()
 			},
 		},