Clean up the basic-authorship crate (#3206)

* Switch consensus-common to new futures

* Fix tests

* More tests fixing

* Make Proposer, OnSlot and SyncOracle mut

* Make the Environment mut as well

* Fix test

* Fix Babe tests

* Babe fixes

* Fix CLI service tests

* Fix Babe tests

* Remove unnecessary trait bound

* Inline the code of BlockBuilder and AuthoringApi

* Remove warning lint

* Bounds simplification

* Imports simplification

* Don't panic on bad generated block

* Code style

* Add doc example

* Remove dependency on aura

* Order dependencies alphabetically

* Minor style

substrate/core/consensus/babe/src/lib.rs

@@ -154,7 +154,7 @@ pub struct BabeParams<C, E, I, SO, SC> {
 	pub block_import: I,
 
 	/// The environment
-	pub env: Arc<E>,
+	pub env: E,
 
 	/// A sync oracle
 	pub sync_oracle: SO,
@@ -220,7 +220,7 @@ pub fn start_babe<B, C, SC, E, I, SO, Error, H>(BabeParams {
 struct BabeWorker<C, E, I, SO> {
 	client: Arc<C>,
 	block_import: Arc<Mutex<I>>,
-	env: Arc<E>,
+	env: E,
 	local_key: Arc<sr25519::Pair>,
 	sync_oracle: SO,
 	force_authoring: bool,
@@ -245,14 +245,13 @@ impl<Hash, H, B, C, E, I, Error, SO> SlotWorker<B> for BabeWorker<C, E, I, SO> w
 	type OnSlot = Pin<Box<dyn Future<Output = Result<(), consensus_common::Error>> + Send>>;
 
 	fn on_slot(
-		&self,
+		&mut self,
 		chain_head: B::Header,
 		slot_info: SlotInfo,
 	) -> Self::OnSlot {
 		let pair = self.local_key.clone();
 		let ref client = self.client;
 		let block_import = self.block_import.clone();
-		let ref env = self.env;
 
 		let (timestamp, slot_number, slot_duration) =
 			(slot_info.timestamp, slot_info.number, slot_info.duration);
@@ -305,7 +304,7 @@ impl<Hash, H, B, C, E, I, Error, SO> SlotWorker<B> for BabeWorker<C, E, I, SO> w
 			);
 
 			// we are the slot author. make a block and sign it.
-			let proposer = match env.init(&chain_head) {
+			let mut proposer = match self.env.init(&chain_head) {
 				Ok(p) => p,
 				Err(e) => {
 					warn!(target: "babe",