use existing utils to instantiate runtime code.

client/service/src/client/client.rs

@@ -1281,12 +1281,7 @@ where
 		if let Some(wasm) = storage.top.get(well_known_keys::CODE) {
 			let mut ext = sp_state_machine::BasicExternalities::new_empty(); // just to read runtime version.
 			let code_fetcher = crate::client::wasm_override::WasmBlob::new(wasm.clone());
-			let hash = code_fetcher.hash.clone();
-			let runtime_code = sp_core::traits::RuntimeCode {
-				code_fetcher: &code_fetcher,
-				heap_pages: None,
-				hash,
-			};
+			let runtime_code = code_fetcher.runtime_code(None);
 			let runtime_version =
 				RuntimeVersionOf::runtime_version(executor, &mut ext, &runtime_code)
 					.map_err(|e| sp_blockchain::Error::VersionInvalid(format!("{:?}", e)))?;

client/service/src/client/wasm_override.rs

@@ -51,7 +51,7 @@ use std::{
 /// Auxiliary structure that holds a wasm blob and its hash.
 pub(crate) struct WasmBlob {
 	code: Vec<u8>,
-	pub(crate) hash: Vec<u8>,
+	hash: Vec<u8>,
 }
 
 impl WasmBlob {
@@ -60,7 +60,7 @@ impl WasmBlob {
 		Self { code, hash }
 	}
 
-	fn runtime_code(&self, heap_pages: Option<u64>) -> RuntimeCode {
+	pub(crate) fn runtime_code(&self, heap_pages: Option<u64>) -> RuntimeCode {
 		RuntimeCode { code_fetcher: self, hash: self.hash.clone(), heap_pages }
 	}
 }