Generate Unit Tests for Benchmarks (#5527)

* Update to latest staking

* generate tests for benchmarking

* add tests, fix warnings

* starting on democracy

* impl_benchmark_tests

* Way more readable

* add test feature flag (does this work?)

* Fix `successful_origin` impl

* democracry benchmark tests

* Fix example benchmarks, add tests

* identity benchmark tests

* Update im-online benchmark tests

* try to add session benchmarking tests (problem with mock)

* staking and timestamp

* add test for treasury, issue with dynamic contains

* utility

* Vesting

* test instead of check

* hide until we figure out what is wrong

* add docs

* close code

* Create custom mock for session-pallet-benchmarking

* Use refcell pattern

* make un-pub

* test-linux-stable includes `runtime-benchmarks` feature

* Revert "test-linux-stable includes `runtime-benchmarks` feature"

This reverts commit a2dab38abd18ac3eb8a6220e4a00e687740bd38c.

* run tests in `--release`

* undo balance change

* build wasm

substrate/frame/support/src/lib.rs

@@ -140,6 +140,8 @@ macro_rules! ord_parameter_types {
 			fn contains(t: &$type) -> bool { &$value == t }
 			fn sorted_members() -> $crate::sp_std::prelude::Vec<$type> { vec![$value] }
 			fn count() -> usize { 1 }
+			#[cfg(feature = "runtime-benchmarks")]
+			fn add(_: &$type) {}
 		}
 	}
 }