Fix elections-phragmen and proxy issue (#7040)

* Fix elections-phragmen and proxy issue

* remove TODO

* Update bond to be per-vote

* Update frame/elections-phragmen/src/lib.rs

* Fix benchmakrs

* Fix weight as well.

* Add license

* Make weight interpreted wasm! 🤦🏻‍♂️

* Remove a bunch of TODOs

* Add migration

* Better storage version.

* Functionify.

* Fix deposit scheme.

* remove legacy bond.

* Master.into()

* better logging.

* Fix benchmarking test

* Fix confused deposit collection.

* Add fine

* Better name for storage item

* Fix name again.

* remove unused

* Update frame/elections-phragmen/src/lib.rs

Co-authored-by: Guillaume Thiolliere <gui.thiolliere@gmail.com>

* Update frame/elections-phragmen/src/lib.rs

Co-authored-by: Guillaume Thiolliere <gui.thiolliere@gmail.com>

* cargo run --release --features runtime-benchmarks --manifest-path bin/node/cli/Cargo.toml -- benchmark --chain dev --steps 50 --repeat 20 --extrinsic * --execution=wasm --wasm-execution=compiled --output ./bin/node/runtime/src/weights --header ./HEADER --pallet pallet_elections_phragmen

* new weight fns

* Fix build

* Fix line width

* fix benchmakrs

* fix warning

* cargo run --release --features runtime-benchmarks --manifest-path bin/node/cli/Cargo.toml -- benchmark --chain dev --steps 50 --repeat 20 --extrinsic * --execution=wasm --wasm-execution=compiled --output ./bin/node/runtime/src/weights --header ./HEADER --pallet pallet_elections_phragmen

* Tune the stake again

* cargo run --release --features runtime-benchmarks --manifest-path bin/node/cli/Cargo.toml -- benchmark --chain dev --steps 50 --repeat 20 --extrinsic * --execution=wasm --wasm-execution=compiled --output ./bin/node/runtime/src/weights --header ./HEADER --pallet pallet_elections_phragmen

* All tests work again.

* A large number of fixes.

* more fixes.

* Fix node build

* Some fixes to benchmarks

* Fix some warnings.

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

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

* Update frame/elections-phragmen/src/lib.rs

Co-authored-by: Guillaume Thiolliere <gui.thiolliere@gmail.com>

* a batch of review comments.

* Fix a test.

* Fix some more tests.

* do migration with pallet version???

* Final touches.

* Remove unused storage.

* another rounds of changes and fixes.

* Update frame/elections-phragmen/src/lib.rs

Co-authored-by: Shawn Tabrizi <shawntabrizi@gmail.com>

* Update frame/elections-phragmen/src/lib.rs

Co-authored-by: Shawn Tabrizi <shawntabrizi@gmail.com>

* Review grumbles.

* Fix a bit more.

* Fix build

* Experimental: independent migration.

* WIP: isolated migration logics

* clean up.

* make migration struct private and move migration to own file

* add doc

* fix StorageInstance new syntax

* Update frame/elections-phragmen/src/migrations_3_0_0.rs

Co-authored-by: Shawn Tabrizi <shawntabrizi@gmail.com>

* another round of self-review.

* bit better formatting

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

* Fix tests.

* Round of self-review

* Clean migrations

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

* Revert unwanted change to construct-runtime

Co-authored-by: Gavin Wood <gavin@parity.io>
Co-authored-by: Guillaume Thiolliere <gui.thiolliere@gmail.com>
Co-authored-by: Shawn Tabrizi <shawntabrizi@gmail.com>
Co-authored-by: Parity Benchmarking Bot <admin@parity.io>

substrate/frame/support/src/traits.rs

@@ -1263,16 +1263,16 @@ pub trait ChangeMembers<AccountId: Clone + Ord> {
 	///
 	/// This resets any previous value of prime.
 	fn set_members_sorted(new_members: &[AccountId], old_members: &[AccountId]) {
-		let (incoming, outgoing) = Self::compute_members_diff(new_members, old_members);
+		let (incoming, outgoing) = Self::compute_members_diff_sorted(new_members, old_members);
 		Self::change_members_sorted(&incoming[..], &outgoing[..], &new_members);
 	}
 
 	/// Compute diff between new and old members; they **must already be sorted**.
 	///
 	/// Returns incoming and outgoing members.
-	fn compute_members_diff(
+	fn compute_members_diff_sorted(
 		new_members: &[AccountId],
-		old_members: &[AccountId]
+		old_members: &[AccountId],
 	) -> (Vec<AccountId>, Vec<AccountId>) {
 		let mut old_iter = old_members.iter();
 		let mut new_iter = new_members.iter();
@@ -1306,6 +1306,11 @@ pub trait ChangeMembers<AccountId: Clone + Ord> {
 
 	/// Set the prime member.
 	fn set_prime(_prime: Option<AccountId>) {}
+
+	/// Get the current prime.
+	fn get_prime() -> Option<AccountId> {
+		None
+	}
 }
 
 impl<T: Clone + Ord> ChangeMembers<T> for () {