Better handling of stable-only build (#6569)

* Better handling of stable-only build

* Fix node template build

* Fix wasm builder node-template version mismatch

* Fix load_spec error

* Add , in parameter

* Add descrptive panic messages in tests

* Add descriptive tests in node/executor benches

* Fix missing compact_code_unwrap

* Add missing wasm_binary_unwrap function for executor integration test

* Only define import_sp_io in no_std

* Small Cargo.toml styling fix

* Bump wasm-builder to 2.0.0

* Fix all `with_wasm_builder_from_crates` version in Substrate

* Use `with_wasm_builder_from_crates` for node-template

Co-authored-by: Gavin Wood <gavin@parity.io>

substrate/bin/node-template/node/src/chain_spec.rs

@@ -38,12 +38,15 @@ pub fn authority_keys_from_seed(s: &str) -> (AuraId, GrandpaId) {
 	)
 }
 
-pub fn development_config() -> ChainSpec {
-	ChainSpec::from_genesis(
+pub fn development_config() -> Result<ChainSpec, String> {
+	let wasm_binary = WASM_BINARY.ok_or("Development wasm binary not available".to_string())?;
+
+	Ok(ChainSpec::from_genesis(
 		"Development",
 		"dev",
 		ChainType::Development,
-		|| testnet_genesis(
+		move || testnet_genesis(
+			wasm_binary,
 			vec![
 				authority_keys_from_seed("Alice"),
 			],
@@ -61,15 +64,18 @@ pub fn development_config() -> ChainSpec {
 		None,
 		None,
 		None,
-	)
+	))
 }
 
-pub fn local_testnet_config() -> ChainSpec {
-	ChainSpec::from_genesis(
+pub fn local_testnet_config() -> Result<ChainSpec, String> {
+	let wasm_binary = WASM_BINARY.ok_or("Development wasm binary not available".to_string())?;
+
+	Ok(ChainSpec::from_genesis(
 		"Local Testnet",
 		"local_testnet",
 		ChainType::Local,
-		|| testnet_genesis(
+		move || testnet_genesis(
+			wasm_binary,
 			vec![
 				authority_keys_from_seed("Alice"),
 				authority_keys_from_seed("Bob"),
@@ -96,16 +102,19 @@ pub fn local_testnet_config() -> ChainSpec {
 		None,
 		None,
 		None,
-	)
+	))
 }
 
-fn testnet_genesis(initial_authorities: Vec<(AuraId, GrandpaId)>,
+fn testnet_genesis(
+	wasm_binary: &[u8],
+	initial_authorities: Vec<(AuraId, GrandpaId)>,
 	root_key: AccountId,
 	endowed_accounts: Vec<AccountId>,
-	_enable_println: bool) -> GenesisConfig {
+	_enable_println: bool,
+) -> GenesisConfig {
 	GenesisConfig {
 		system: Some(SystemConfig {
-			code: WASM_BINARY.to_vec(),
+			code: wasm_binary.to_vec(),
 			changes_trie_config: Default::default(),
 		}),
 		balances: Some(BalancesConfig {