Benchmark Democracy Pallet (#5257)

* Add origin bounds to benchmark macro.

* Add democracy benchmark.

* Fix tests

* Remove collective from frame/benchmarking, partially use EnsureOrigin.

* Remove collective stuff.

* Make previous benches compile again.

* Remove comments.

* Make prev bench to work again.

* Add remove votes.

* Add new proxy calls.

* Add runtime-benchmarks guard to EnsureOrigin and implementations.

* Refactor.

* Add missing import.

* Remove duplicated import

* Fix features.

* Add some missing features.

* Update frame/collective/Cargo.toml

Co-Authored-By: Kian Paimani <5588131+kianenigma@users.noreply.github.com>

* Update frame/democracy/src/benchmarking.rs

Co-Authored-By: Kian Paimani <5588131+kianenigma@users.noreply.github.com>

* Update frame/democracy/src/benchmarking.rs

Co-Authored-By: Kian Paimani <5588131+kianenigma@users.noreply.github.com>

* Add referendums to state.

* populate vecs before call

* Update weight docs

* More fixes and weight docs

* More updates

Co-authored-by: Kian Paimani <5588131+kianenigma@users.noreply.github.com>
Co-authored-by: Shawn Tabrizi <shawntabrizi@gmail.com>

substrate/primitives/runtime/Cargo.toml

@@ -32,6 +32,7 @@ rand = "0.7.2"
 
 [features]
 bench = []
+runtime-benchmarks = []
 default = ["std"]
 std = [
 	"sp-application-crypto/std",

substrate/primitives/runtime/src/traits.rs

@@ -157,6 +157,12 @@ pub trait EnsureOrigin<OuterOrigin> {
 	}
 	/// Perform the origin check.
 	fn try_origin(o: OuterOrigin) -> result::Result<Self::Success, OuterOrigin>;
+
+	/// Returns an outer origin capable of passing `try_origin` check.
+	/// 
+	/// ** Should be used for benchmarking only!!! **
+	#[cfg(feature = "runtime-benchmarks")]
+	fn successful_origin() -> OuterOrigin;
 }
 
 /// An error that indicates that a lookup failed.