Backports for beta 2.2.2 (#9976)

* version: bump beta to 2.2.2

* Add experimental RPCs flag (#9928)

* WiP

* Enable experimental RPCs.

* Keep existing blocks when restoring a Snapshot (#8643)

* Rename db_restore => client

* First step: make it compile!

* Second step: working implementation!

* Refactoring

* Fix tests

* PR Grumbles

* PR Grumbles WIP

* Migrate ancient blocks interating backward

* Early return in block migration if snapshot is aborted

* Remove RwLock getter (PR Grumble I)

* Remove dependency on `Client`: only used Traits

* Add test for recovering aborted snapshot recovery

* Add test for migrating old blocks

* Fix build

* PR Grumble I

* PR Grumble II

* PR Grumble III

* PR Grumble IV

* PR Grumble V

* PR Grumble VI

* Fix one test

* Fix test

* PR Grumble

* PR Grumbles

* PR Grumbles II

* Fix tests

* Release RwLock earlier

* Revert Cargo.lock

* Update _update ancient block_ logic: set local in `commit`

* Update typo in ethcore/src/snapshot/service.rs

Co-Authored-By: ngotchac <ngotchac@gmail.com>

* Adjust requests costs for light client (#9925)

* PIP Table Cost relative to average peers instead of max peers

* Add tracing in PIP new_cost_table

* Update stat peer_count

* Use number of leeching peers for Light serve costs

* Fix test::light_params_load_share_depends_on_max_peers (wrong type)

* Remove (now) useless test

* Remove `load_share` from LightParams.Config
Prevent div. by 0

* Add LEECHER_COUNT_FACTOR

* PR Grumble: u64 to u32 for f64 casting

* Prevent u32 overflow for avg_peer_count

* Add tests for LightSync::Statistics

* Fix empty steps (#9939)

* Don't send empty step twice or empty step then block.

* Perform basic validation of locally sealed blocks.

* Don't include empty step twice.

* prevent silent errors in daemon mode, closes #9367 (#9946)

* Fix a deadlock (#9952)

* Update informant:
  - decimal in Mgas/s
  - print every 5s (not randomly between 5s and 10s)

* Fix dead-lock in `blockchain.rs`

* Update locks ordering

* Fix light client informant while syncing (#9932)

* Add `is_idle` to LightSync to check importing status

* Use SyncStateWrapper to make sure is_idle gets updates

* Update is_major_import to use verified queue size as well

* Add comment for `is_idle`

* Add Debug to `SyncStateWrapper`

* `fn get` -> `fn into_inner`

*  ci: rearrange pipeline by logic (#9970)

* ci: rearrange pipeline by logic

* ci: rename docs script

* fix docker build (#9971)

* Deny unknown fields for chainspec (#9972)

* Add deny_unknown_fields to chainspec

* Add tests and fix existing one

* Remove serde_ignored dependency for chainspec

* Fix rpc test eth chain spec

* Fix starting_nonce_test spec

* Improve block and transaction propagation (#9954)

* Refactor sync to add priority tasks.

* Send priority tasks notifications.

* Propagate blocks, optimize transactions.

* Implement transaction propagation. Use sync_channel.

* Tone down info.

* Prevent deadlock by not waiting forever for sync lock.

* Fix lock order.

* Don't use sync_channel to prevent deadlocks.

* Fix tests.

* Fix unstable peers and slowness in sync (#9967)

* Don't sync all peers after each response

* Update formating

* Fix tests: add `continue_sync` to `Sync_step`

* Update ethcore/sync/src/chain/mod.rs

Co-Authored-By: ngotchac <ngotchac@gmail.com>

* fix rpc middlewares

* fix Cargo.lock

* json: resolve merge in spec

* rpc: fix starting_nonce_test

* ci: allow nightl job to fail

parity/cli/mod.rs

@@ -467,6 +467,10 @@ usage! {
 			"--no-jsonrpc",
 			"Disable the HTTP JSON-RPC API server.",
 
+			FLAG flag_jsonrpc_experimental: (bool) = false, or |c: &Config| c.rpc.as_ref()?.experimental_rpcs.clone(),
+			"--jsonrpc-experimental",
+			"Enable experimental RPCs. Enable to have access to methods from unfinalised EIPs in all namespaces",
+
 			ARG arg_jsonrpc_port: (u16) = 8545u16, or |c: &Config| c.rpc.as_ref()?.port.clone(),
 			"--jsonrpc-port=[PORT]",
 			"Specify the port portion of the HTTP JSON-RPC API server.",
@@ -1141,7 +1145,7 @@ struct Operating {
 	no_persistent_txqueue: Option<bool>,
 	no_hardcoded_sync: Option<bool>,
 
-	#[serde(rename="public_node")]
+	#[serde(rename = "public_node")]
 	_legacy_public_node: Option<bool>,
 }
 
@@ -1173,15 +1177,15 @@ struct PrivateTransactions {
 struct Ui {
 	path: Option<String>,
 
-	#[serde(rename="force")]
+	#[serde(rename = "force")]
 	_legacy_force: Option<bool>,
-	#[serde(rename="disable")]
+	#[serde(rename = "disable")]
 	_legacy_disable: Option<bool>,
-	#[serde(rename="port")]
+	#[serde(rename = "port")]
 	_legacy_port: Option<u16>,
-	#[serde(rename="interface")]
+	#[serde(rename = "interface")]
 	_legacy_interface: Option<String>,
-	#[serde(rename="hosts")]
+	#[serde(rename = "hosts")]
 	_legacy_hosts: Option<Vec<String>>,
 }
 
@@ -1219,6 +1223,7 @@ struct Rpc {
 	server_threads: Option<usize>,
 	processing_threads: Option<usize>,
 	max_payload: Option<usize>,
+	experimental_rpcs: Option<bool>,
 }
 
 #[derive(Default, Debug, PartialEq, Deserialize)]
@@ -1244,21 +1249,21 @@ struct Ipc {
 #[derive(Default, Debug, PartialEq, Deserialize)]
 #[serde(deny_unknown_fields)]
 struct Dapps {
-	#[serde(rename="disable")]
+	#[serde(rename = "disable")]
 	_legacy_disable: Option<bool>,
-	#[serde(rename="port")]
+	#[serde(rename = "port")]
 	_legacy_port: Option<u16>,
-	#[serde(rename="interface")]
+	#[serde(rename = "interface")]
 	_legacy_interface: Option<String>,
-	#[serde(rename="hosts")]
+	#[serde(rename = "hosts")]
 	_legacy_hosts: Option<Vec<String>>,
-	#[serde(rename="cors")]
+	#[serde(rename = "cors")]
 	_legacy_cors: Option<String>,
-	#[serde(rename="path")]
+	#[serde(rename = "path")]
 	_legacy_path: Option<String>,
-	#[serde(rename="user")]
+	#[serde(rename = "user")]
 	_legacy_user: Option<String>,
-	#[serde(rename="pass")]
+	#[serde(rename = "pass")]
 	_legacy_pass: Option<String>,
 }
 
@@ -1676,6 +1681,7 @@ mod tests {
 			// -- API and Console Options
 			// RPC
 			flag_no_jsonrpc: false,
+			flag_jsonrpc_experimental: false,
 			arg_jsonrpc_port: 8545u16,
 			arg_jsonrpc_interface: "local".into(),
 			arg_jsonrpc_cors: "null".into(),
@@ -1958,6 +1964,7 @@ mod tests {
 				server_threads: None,
 				processing_threads: None,
 				max_payload: None,
+				experimental_rpcs: None,
 			}),
 			ipc: Some(Ipc {
 				disable: None,