EIP 1283: Net gas metering for SSTORE without dirty maps (#9319)

* Implement last_checkpoint_storage_at

* Add reverted_storage_at for externalities

* sstore_clears_count -> sstore_clears_refund

* Implement eip1283 for evm

* Add eip1283Transition params

* evm: fix tests

* jsontests: fix test

* Return checkpoint index when creating

* Comply with spec Version II

* Fix docs

* Fix jsontests feature compile

* Address grumbles

* Fix no-checkpoint-entry case

* Remove unnecessary expect

* Add test for State::checkpoint_storage_at

* Add executive level test for eip1283

* Hard-code transaction_checkpoint_index to 0

* Fix jsontests

* Add tests for checkpoint discard/revert

* Require checkpoint to be empty for kill_account and commit

* Get code coverage

* Use saturating_add/saturating_sub

* Fix issues in insert_cache

* Clear the state again

* Fix original_storage_at

* Early return for empty RLP trie storage

* Update comments

* Fix borrow_mut issue

* Simplify checkpoint_storage_at if branches

* Better commenting for gas handling code

* Address naming grumbles

* More tests

* Fix an issue in overwrite_with

* Add another test

* Fix comment

* Remove unnecessary bracket

* Move orig to inner if

* Remove test coverage for this PR

* Add tests for executive original value

* Add warn! for an unreachable cause

json/src/spec/params.rs

@@ -109,6 +109,8 @@ pub struct Params {
 	#[serde(rename="eip1052Transition")]
 	pub eip1052_transition: Option<Uint>,
 	/// See `CommonParams` docs.
+	#[serde(rename="eip1283Transition")]
+	pub eip1283_transition: Option<Uint>,
 	#[serde(rename="eip1014Transition")]
 	pub eip1014_transition: Option<Uint>,
 	/// See `CommonParams` docs.