Refactor away from opaque hashes (#5226)

* System.BlockHash

* Fix hash

* Introduce K/V iteration in all _concat maps

Also move across:
- System.Account (blake2_128_concat)
- Balances.Locks (twox_64_concat)
- ElectionsPhragmen.VotesOf (twox_64_concat)
- ElectionsPhragmen.StakeOf (twox_64_concat)
- Identity.IdentityOf (twox_64_concat)
- Identity.SubsOf (twox_64_concat)
- Society.Payouts (twox_64_concat)
- Session.NextKeys (twox_64_concat)
- Identity.SuperOf (blake2_128_concat)
- Session.KeyOwner (blake2_128_concat)
- Society.SuspendedCandidates (twox_64_concat)
- Society.SuspendedMembers (twox_64_concat)
- Society.Vouching (twox_64_concat)
- Society.Strikes (twox_64_concat)
- System.EventTopics
- Balances.Account

* Build fixes

* Ensure migration happens in correct order

* Staking.*

* Vesting.* Offences.*

* Democracy.*

* Babe.* Collective.*

* Grandpa.*

* Assets.* Benchmark.* Contracts.* Elections.* Asset.* Nicks.*

Also introduce real account list

* ImOnline.*

* Treasury.*

* Recovery.*

* Final bits.

* Docs

* Fix one test

* Fix test

* All passing except the UI tests

* Remove linked_map part 1

* Remove linked_map

* Some iterator utils for double maps.

* Remove old migrations

* Introduce tombstone for LinkedMap type

* Migration for genesis hash

* Fix build

* Fix hash

* Rename Map is_linked -> unused, keeping backwards compat (#5256)

* Update frame/balances/src/lib.rs

Co-Authored-By: Shawn Tabrizi <shawntabrizi@gmail.com>

* Update frame/elections/src/lib.rs

Co-Authored-By: Shawn Tabrizi <shawntabrizi@gmail.com>

* Remove old migration code.

* Update frame/system/src/lib.rs

Co-Authored-By: Shawn Tabrizi <shawntabrizi@gmail.com>

* Update bin/node/runtime/src/lib.rs

Co-Authored-By: Shawn Tabrizi <shawntabrizi@gmail.com>

* Fix hash

* fix session migration

* Fix watning

Co-authored-by: Jaco Greeff <jacogr@gmail.com>
Co-authored-by: Shawn Tabrizi <shawntabrizi@gmail.com>
Co-authored-by: Robert Habermeier <rphmeier@gmail.com>

substrate/frame/elections/src/lib.rs

@@ -236,16 +236,16 @@ decl_storage! {
 		// [`all_approvals_of`]. Furthermore, each vector of scalars is chunked with the cap of
 		// `APPROVAL_SET_SIZE`.
 		pub ApprovalsOf get(fn approvals_of):
-			map hasher(blake2_256) (T::AccountId, SetIndex) => Vec<ApprovalFlag>;
+			map hasher(twox_64_concat) (T::AccountId, SetIndex) => Vec<ApprovalFlag>;
 		/// The vote index and list slot that the candidate `who` was registered or `None` if they
 		/// are not currently registered.
 		pub RegisterInfoOf get(fn candidate_reg_info):
-			map hasher(blake2_256) T::AccountId => Option<(VoteIndex, u32)>;
+			map hasher(twox_64_concat) T::AccountId => Option<(VoteIndex, u32)>;
 		/// Basic information about a voter.
 		pub VoterInfoOf get(fn voter_info):
-			map hasher(blake2_256) T::AccountId => Option<VoterInfo<BalanceOf<T>>>;
+			map hasher(twox_64_concat) T::AccountId => Option<VoterInfo<BalanceOf<T>>>;
 		/// The present voter list (chunked and capped at [`VOTER_SET_SIZE`]).
-		pub Voters get(fn voters): map hasher(blake2_256) SetIndex => Vec<Option<T::AccountId>>;
+		pub Voters get(fn voters): map hasher(twox_64_concat) SetIndex => Vec<Option<T::AccountId>>;
 		/// the next free set to store a voter in. This will keep growing.
 		pub NextVoterSet get(fn next_nonfull_voter_set): SetIndex = 0;
 		/// Current number of Voters.
@@ -266,7 +266,7 @@ decl_storage! {
 
 		/// Who is able to vote for whom. Value is the fund-holding account, key is the
 		/// vote-transaction-sending account.
-		pub Proxy get(fn proxy): map hasher(blake2_256) T::AccountId => Option<T::AccountId>;
+		pub Proxy get(fn proxy): map hasher(blake2_128_concat) T::AccountId => Option<T::AccountId>;
 	}
 }
 

substrate/frame/elections/src/mock.rs

@@ -55,7 +55,7 @@ impl frame_system::Trait for Test {
 	type Version = ();
 	type ModuleToIndex = ();
 	type AccountData = pallet_balances::AccountData<u64>;
-	type OnNewAccount = ();
+	type MigrateAccount = (); type OnNewAccount = ();
 	type OnKilledAccount = ();
 }