state_machine no_std witness externalities (#6934)

* checkpoint before removing CT from change trie

* before trie backend without tx

* undo

* Started no transaction, but would need using a different root
calculation method, out of the scope of this pr, will roll back.

* Remove NoTransaction.

* partially address review.
dummy stats implementation for no_std.

* Remove ChangeTrieOverlay.

* modified function

* Remove witness_ext

* need noops changes root

* update from cumulus branch

* line break

* remove warning

* line break

* From review: renamings and stats active in no std (except time).

* include cache, exclude change trie cache with individual temporary bad looking
no_std check

* little test

* fuse imports and filter_map prepare_extrinsics_input_inner fold.

* put back ExtInner into Ext, awkward double proto for new function.

* Apply suggestions from code review

* Update primitives/state-machine/Cargo.toml

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

substrate/primitives/state-machine/src/changes_trie/build.rs

@@ -140,8 +140,15 @@ fn prepare_extrinsics_input_inner<'a, B, H, Number>(
 		Number: BlockNumber,
 {
 	changes
-		.filter(|( _, v)| v.extrinsics().next().is_some())
-		.try_fold(BTreeMap::new(), |mut map: BTreeMap<&[u8], (ExtrinsicIndex<Number>, Vec<u32>)>, (k, v)| {
+		.filter_map(|(k, v)| {
+			let extrinsics = v.extrinsics();
+			if !extrinsics.is_empty() {
+				Some((k, extrinsics))
+			} else {
+				None
+			}
+		})
+		.try_fold(BTreeMap::new(), |mut map: BTreeMap<&[u8], (ExtrinsicIndex<Number>, Vec<u32>)>, (k, extrinsics)| {
 			match map.entry(k) {
 				Entry::Vacant(entry) => {
 					// ignore temporary values (values that have null value at the end of operation
@@ -161,7 +168,7 @@ fn prepare_extrinsics_input_inner<'a, B, H, Number>(
 						}
 					};
 
-					let extrinsics = v.extrinsics().cloned().collect();
+					let extrinsics = extrinsics.into_iter().collect();
 					entry.insert((ExtrinsicIndex {
 						block: block.clone(),
 						key: k.to_vec(),
@@ -170,11 +177,11 @@ fn prepare_extrinsics_input_inner<'a, B, H, Number>(
 				Entry::Occupied(mut entry) => {
 					// we do not need to check for temporary values here, because entry is Occupied
 					// AND we are checking it before insertion
-					let extrinsics = &mut entry.get_mut().1;
-					extrinsics.extend(
-						v.extrinsics().cloned()
+					let entry_extrinsics = &mut entry.get_mut().1;
+					entry_extrinsics.extend(
+						extrinsics.into_iter()
 					);
-					extrinsics.sort();
+					entry_extrinsics.sort();
 				},
 			}
 

substrate/primitives/state-machine/src/changes_trie/mod.rs

@@ -85,9 +85,6 @@ use crate::{
 	},
 };
 
-/// Changes that are made outside of extrinsics are marked with this index;
-pub const NO_EXTRINSIC_INDEX: u32 = 0xffffffff;
-
 /// Requirements for block number that can be used with changes tries.
 pub trait BlockNumber:
 	Send + Sync + 'static +