contracts: Expose rent parameter to contracts (#8231)

* contracts: Expose rent parameter to contracts

* cargo run --release --features=runtime-benchmarks --manifest-path=bin/node/cli/Cargo.toml -- benchmark --chain=dev --steps=50 --repeat=20 --pallet=pallet_contracts --extrinsic=* --execution=wasm --wasm-execution=compiled --heap-pages=4096 --output=./frame/contracts/src/weights.rs --template=./.maintain/frame-weight-template.hbs

* Fix typos

* Improve comments

* Add rent parameter weights

* Allow deploying a new schedule with the same version

* Add storage migration for new schedule

* Only decode the schedule version in storage migration

* Remove confusing docs

* Replace original_code_len() by aggregate_code_len()

Co-authored-by: Parity Benchmarking Bot <admin@parity.io>

frame/contracts/CHANGELOG.md

@@ -16,7 +16,13 @@ The interface provided to smart contracts will adhere to semver with one excepti
 major version bumps will be backwards compatible with regard to already deployed contracts.
 In other words: Upgrading this pallet will not break pre-existing contracts.
 
-## [v3.0.0]
+## [Unreleased]
+
+### Added
+
+- Add `seal_rent_params` contract callable function.
+
+## [v3.0.0] 2021-02-25
 
 This version constitutes the first release that brings any stability guarantees (see above).
 

frame/contracts/src/benchmarking/mod.rs

@@ -533,6 +533,14 @@ benchmarks! {
 		let origin = RawOrigin::Signed(instance.caller.clone());
 	}: call(origin, instance.addr, 0u32.into(), Weight::max_value(), vec![])
 
+	seal_rent_params {
+		let r in 0 .. API_BENCHMARK_BATCHES;
+		let instance = Contract::<T>::new(WasmModule::getter(
+			"seal_rent_params", r * API_BENCHMARK_BATCH_SIZE
+		), vec![], Endow::Max)?;
+		let origin = RawOrigin::Signed(instance.caller.clone());
+	}: call(origin, instance.addr, 0u32.into(), Weight::max_value(), vec![])
+
 	seal_weight_to_fee {
 		let r in 0 .. API_BENCHMARK_BATCHES;
 		let pages = code::max_pages::<T>();