State metrics possible changes (#5168)

* Registering state from overlay.

* fix

* fix2

* Apply suggestions from code review

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

substrate/client/src/call_executor.rs

@@ -160,36 +160,38 @@ where
 					recorder.clone(),
 				);
 
-				StateMachine::new(
+				let changes = &mut *changes.borrow_mut();
+				let mut state_machine = StateMachine::new(
 					&backend,
 					changes_trie_state,
-					&mut *changes.borrow_mut(),
+					changes,
 					&self.executor,
 					method,
 					call_data,
 					extensions.unwrap_or_default(),
 					&runtime_code,
 					self.spawn_handle.clone(),
-				)
+				);
 				// TODO: https://github.com/paritytech/substrate/issues/4455
 				// .with_storage_transaction_cache(storage_transaction_cache.as_mut().map(|c| &mut **c))
-				.execute_using_consensus_failure_handler(execution_manager, native_call)
+				state_machine.execute_using_consensus_failure_handler(execution_manager, native_call)
 			},
 			None => {
 				let state_runtime_code = sp_state_machine::backend::BackendRuntimeCode::new(&state);
-				StateMachine::new(
+				let runtime_code = state_runtime_code.runtime_code()?;
+				let changes = &mut *changes.borrow_mut();
+				let mut state_machine = StateMachine::new(
 					&state,
 					changes_trie_state,
-					&mut *changes.borrow_mut(),
+					changes,
 					&self.executor,
 					method,
 					call_data,
 					extensions.unwrap_or_default(),
-					&state_runtime_code.runtime_code()?,
+					&runtime_code,
 					self.spawn_handle.clone(),
-				)
-				.with_storage_transaction_cache(storage_transaction_cache.as_mut().map(|c| &mut **c))
-				.execute_using_consensus_failure_handler(execution_manager, native_call)
+				).with_storage_transaction_cache(storage_transaction_cache.as_mut().map(|c| &mut **c));
+				state_machine.execute_using_consensus_failure_handler(execution_manager, native_call)
 			}
 		}.map_err(Into::into)
 	}

substrate/client/src/light/backend.rs

@@ -505,6 +505,12 @@ impl<H: Hasher> StateBackend<H> for GenesisOrUnavailableState<H>
 		}
 	}
 
+	fn register_overlay_stats(&mut self, _stats: &sp_state_machine::StateMachineStats) { }
+
+	fn usage_info(&self) -> sp_state_machine::UsageInfo {
+		sp_state_machine::UsageInfo::empty()
+	}
+
 	fn as_trie_backend(&mut self) -> Option<&TrieBackend<Self::TrieBackendStorage, H>> {
 		match self {
 			GenesisOrUnavailableState::Genesis(ref mut state) => state.as_trie_backend(),