fix test collator compilation failure (#89)

* fix test collator compilation failure

Closes #88.

* copy method instead of using feature

Using a feature gate like "test-features" is problematic because
it is leaky: depending on situational considitons such as the
current working directory when compilation is attempted, the
feature may or may not be applied, which makes success inconsistent.
It's simpler in this case to copy a dozen lines of code than to
work out all the issues with test features.

test/parachain/src/command.rs

@@ -23,12 +23,11 @@ use sc_cli::{
 	CliConfiguration, Error, ImportParams, KeystoreParams, NetworkParams, Result, SharedParams,
 	SubstrateCli,
 };
-use sc_service::client::genesis;
 use sc_network::config::TransportConfig;
 use sc_service::config::{NetworkConfiguration, NodeKeyConfig, PrometheusConfig};
 use sp_core::hexdisplay::HexDisplay;
 use sp_runtime::{
-	traits::{Block as BlockT, Hash as HashT, Header as HeaderT},
+	traits::{Block as BlockT, Hash as HashT, Header as HeaderT, Zero},
 	BuildStorage,
 };
 use std::net::SocketAddr;
@@ -137,7 +136,22 @@ pub fn run() -> Result<()> {
 			let state_root = <<<Block as BlockT>::Header as HeaderT>::Hashing as HashT>::trie_root(
 				storage.top.clone().into_iter().chain(child_roots).collect(),
 			);
-			let block: Block = genesis::construct_genesis_block(state_root);
+			let block = {
+				let extrinsics_root = <<<Block as BlockT>::Header as HeaderT>::Hashing as HashT>::trie_root(
+					Vec::new(),
+				);
+			
+				Block::new(
+					<<Block as BlockT>::Header as HeaderT>::new(
+						Zero::zero(),
+						extrinsics_root,
+						state_root,
+						Default::default(),
+						Default::default(),
+					),
+					Default::default(),
+				)
+			};
 
 			let header_hex = format!("0x{:?}", HexDisplay::from(&block.header().encode()));