Correctly serialize code in chain spec as hex.

Due to a bug, the runtime code was previously serialized as a JSON
array of numbers, pretty printed one byte per line.

srml/support/procedural/src/storage/genesis_config/genesis_config_def.rs

@@ -23,9 +23,9 @@ use quote::quote;
 use super::super::{DeclStorageDefExt, StorageLineTypeDef};
 
 pub struct GenesisConfigFieldDef {
-	pub doc: Vec<syn::Meta>,
 	pub name: syn::Ident,
 	pub typ: syn::Type,
+	pub attrs: Vec<syn::Meta>,
 	pub default: TokenStream,
 }
 
@@ -114,17 +114,16 @@ impl GenesisConfigDef {
 				.unwrap_or_else(|| quote!( Default::default() ));
 
 			config_field_defs.push(GenesisConfigFieldDef {
-				doc: line.doc_attrs.clone(),
 				name: config_field,
 				typ,
+				attrs: line.doc_attrs.clone(),
 				default,
 			});
 		}
 
 		for line in &def.extra_genesis_config_lines {
-			let doc = line.attrs.iter()
-				.filter_map(|a| a.parse_meta().ok())
-				.filter(|m| m.name() == "doc")
+			let attrs = line.attrs.iter()
+				.map(|a| a.parse_meta().expect("attribute cannot be parsed"))
 				.collect();
 
 			let default = line.default.as_ref().map(|e| quote!( #e ))
@@ -132,9 +131,9 @@ impl GenesisConfigDef {
 
 
 			config_field_defs.push(GenesisConfigFieldDef {
-				doc,
 				name: line.name.clone(),
 				typ: line.typ.clone(),
+				attrs,
 				default,
 			});
 		}

srml/support/procedural/src/storage/genesis_config/mod.rs

@@ -33,13 +33,13 @@ fn decl_genesis_config_and_impl_default(
 	genesis_config: &GenesisConfigDef,
 ) -> TokenStream {
 	let config_fields = genesis_config.fields.iter().map(|field| {
-		let (name, typ, doc) = (&field.name, &field.typ, &field.doc);
-		quote!( #( #[ #doc] )* pub #name: #typ, )
+		let (name, typ, attrs) = (&field.name, &field.typ, &field.attrs);
+		quote!( #( #[ #attrs] )* pub #name: #typ, )
 	});
 
 	let config_field_defaults = genesis_config.fields.iter().map(|field| {
-		let (name, default, doc) = (&field.name, &field.default, &field.doc);
-		quote!( #( #[ #doc] )* #name: #default, )
+		let (name, default) = (&field.name, &field.default);
+		quote!( #name: #default, )
 	});
 
 	let serde_bug_bound = if !genesis_config.fields.is_empty() {