Companion for Substrate #5961 (on_offence weight) (#1103)

* Add new trait to offences

* companion for substrate#6069

* update to latest changes

* Update Cargo.lock

Co-authored-by: André Silva <andre.beat@gmail.com>
Co-authored-by: Gav Wood <gavin@parity.io>

polkadot/runtime/kusama/src/lib.rs

@@ -56,6 +56,7 @@ use sp_staking::SessionIndex;
 use frame_support::{
 	parameter_types, construct_runtime, debug,
 	traits::{KeyOwnerProofSystem, SplitTwoWays, Randomness, LockIdentifier},
+	weights::Weight,
 };
 use im_online::sr25519::AuthorityId as ImOnlineId;
 use authority_discovery_primitives::AuthorityId as AuthorityDiscoveryId;
@@ -476,10 +477,15 @@ impl treasury::Trait for Runtime {
 	type ModuleId = TreasuryModuleId;
 }
 
+parameter_types! {
+	pub const OffencesWeightSoftLimit: Weight = Perbill::from_percent(60) * MaximumBlockWeight::get();
+}
+
 impl offences::Trait for Runtime {
 	type Event = Event;
 	type IdentificationTuple = session::historical::IdentificationTuple<Self>;
 	type OnOffenceHandler = Staking;
+	type WeightSoftLimit = OffencesWeightSoftLimit;
 }
 
 impl authority_discovery::Trait for Runtime {}