chain-spec: getting ready for native-runtime-free world (#1256)

This PR prepares chains specs for _native-runtime-free_  world.

This PR has following changes:
- `substrate`:
  - adds support for:
- JSON based `GenesisConfig` to `ChainSpec` allowing interaction with
runtime `GenesisBuilder` API.
- interacting with arbitrary runtime wasm blob to[
`chain-spec-builder`](https://github.com/paritytech/substrate/blob/3ef576eaeb3f42610e85daecc464961cf1295570/bin/utils/chain-spec-builder/src/lib.rs#L46)
command line util,
- removes
[`code`](https://github.com/paritytech/substrate/blob/3ef576eaeb3f42610e85daecc464961cf1295570/frame/system/src/lib.rs#L660)
from `system_pallet`
  - adds `code` to the `ChainSpec`
- deprecates
[`ChainSpec::from_genesis`](https://github.com/paritytech/substrate/blob/3ef576eaeb3f42610e85daecc464961cf1295570/client/chain-spec/src/chain_spec.rs#L263),
but also changes the signature of this method extending it with `code`
argument.
[`ChainSpec::builder()`](https://github.com/paritytech/substrate/blob/20bee680ed098be7239cf7a6b804cd4de267983e/client/chain-spec/src/chain_spec.rs#L507)
should be used instead.
- `polkadot`:
- all references to `RuntimeGenesisConfig` in `node/service` are
removed,
- all
`(kusama|polkadot|versi|rococo|wococo)_(staging|dev)_genesis_config`
functions now return the JSON patch for default runtime `GenesisConfig`,
  - `ChainSpecBuilder` is used, `ChainSpec::from_genesis` is removed,

- `cumulus`:
  - `ChainSpecBuilder` is used, `ChainSpec::from_genesis` is removed,
- _JSON_ patch configuration used instead of `RuntimeGenesisConfig
struct` in all chain specs.
  
---------

Co-authored-by: command-bot <>
Co-authored-by: Javier Viola <javier@parity.io>
Co-authored-by: Davide Galassi <davxy@datawok.net>
Co-authored-by: Francisco Aguirre <franciscoaguirreperez@gmail.com>
Co-authored-by: Kevin Krone <kevin@parity.io>
Co-authored-by: Bastian Köcher <git@kchr.de>

cumulus/test/client/src/lib.rs

@@ -19,13 +19,13 @@
 mod block_builder;
 use codec::{Decode, Encode};
 use runtime::{
-	Balance, Block, BlockHashCount, Runtime, RuntimeCall, RuntimeGenesisConfig, Signature,
-	SignedExtra, SignedPayload, UncheckedExtrinsic, VERSION,
+	Balance, Block, BlockHashCount, Runtime, RuntimeCall, Signature, SignedExtra, SignedPayload,
+	UncheckedExtrinsic, VERSION,
 };
 use sc_executor::HeapAllocStrategy;
 use sc_executor_common::runtime_blob::RuntimeBlob;
 use sp_blockchain::HeaderBackend;
-use sp_core::{sr25519, Pair};
+use sp_core::Pair;
 use sp_io::TestExternalities;
 use sp_runtime::{generic::Era, BuildStorage, SaturatedConversion};
 
@@ -84,17 +84,12 @@ pub struct GenesisParameters {
 
 impl substrate_test_client::GenesisInit for GenesisParameters {
 	fn genesis_storage(&self) -> Storage {
-		if self.endowed_accounts.is_empty() {
-			genesis_config().build_storage().unwrap()
-		} else {
-			cumulus_test_service::testnet_genesis(
-				cumulus_test_service::get_account_id_from_seed::<sr25519::Public>("Alice"),
-				self.endowed_accounts.clone(),
-				None,
-			)
-			.build_storage()
-			.unwrap()
-		}
+		cumulus_test_service::chain_spec::get_chain_spec_with_extra_endowed(
+			None,
+			self.endowed_accounts.clone(),
+		)
+		.build_storage()
+		.expect("Builds test runtime genesis storage")
 	}
 }
 
@@ -127,10 +122,6 @@ impl DefaultTestClientBuilderExt for TestClientBuilder {
 	}
 }
 
-fn genesis_config() -> RuntimeGenesisConfig {
-	cumulus_test_service::testnet_genesis_with_default_endowed(Default::default(), None)
-}
-
 /// Create an unsigned extrinsic from a runtime call.
 pub fn generate_unsigned(function: impl Into<RuntimeCall>) -> UncheckedExtrinsic {
 	UncheckedExtrinsic::new_unsigned(function.into())