Grandpa validator set handoff justification (#1190)

* core: make block justification optional

* runtime: update wasm binaries

* core: optionally pass justification on finalize_block

* finality-grandpa: add channel to trigger authority set changes

this will allow the `BlockImport` to trigger an authority set change when
importing a change block that provides a justification (when syncing)

* finality-grandpa: move finalize_block to free function

* finality-grandpa: add GrandpaOracle for auth set liveness checking

this will be used by `BlockImport` to check whether the authority set for a
given block is still live, if the authority set isn't live then importing a
change block requires a justification.

* finality-grandpa: store justification on finalized transition blocks

* finality-grandpa: check justification on authority set change blocks

* finality-grandpa: poll grandpa liveness oracle every 10 seconds

* finality-grandpa: spawn grandpa oracle in service setup

* core: support multiple subscriptions per consensus gossip topic

* finality-grandpa: create and verify justifications

* finality-grandpa: update to local branch of grandpa

* finality-grandpa: update to finality-grandpa v0.5.0

* finality-grandpa: move grandpa oracle code

* finality-grandpa: fix canonality check

* finality-grandpa: clean up error handling

* finality-grandpa: fix canonical_at_height

* finality-grandpa: fix tests

* runtime: update wasm binaries

* core: add tests for finalizing block with justification

* finality-grandpa: improve validation of justifications

* core: remove unused IncompleteJustification block import error

* core: test multiple subscribers for same consensus gossip topic

* Revert "finality-grandpa: improve validation of justifications"

This reverts commit 51eb2c58c2219801e876af6d6c9371bdd9ff2477.

* finality-grandpa: fix commit validation

* finality-grandpa: fix commit ancestry validation

* finality-grandpa: use grandpa v0.5.1

* finality-grandpa: add docs

* finality-grandpa: fix failing test

* finality-grandpa: only allow a pending authority set change per fork

* finality-grandpa: fix validator set transition test

substrate/node/runtime/wasm/Cargo.lock

@@ -326,10 +326,10 @@ dependencies = [
 [[package]]
 name = "kvdb"
 version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
+source = "git+https://github.com/paritytech/parity-common?rev=616b40150ded71f57f650067fcbc5c99d7c343e6#616b40150ded71f57f650067fcbc5c99d7c343e6"
 dependencies = [
  "elastic-array 0.10.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "parity-bytes 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "parity-bytes 0.1.0 (git+https://github.com/paritytech/parity-common?rev=616b40150ded71f57f650067fcbc5c99d7c343e6)",
 ]
 
 [[package]]
@@ -586,7 +586,7 @@ dependencies = [
 [[package]]
 name = "parity-bytes"
 version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
+source = "git+https://github.com/paritytech/parity-common?rev=616b40150ded71f57f650067fcbc5c99d7c343e6#616b40150ded71f57f650067fcbc5c99d7c343e6"
 
 [[package]]
 name = "parity-codec"
@@ -1179,7 +1179,6 @@ version = "0.1.0"
 dependencies = [
  "hex-literal 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "parity-codec 2.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "parity-codec-derive 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.79 (registry+https://github.com/rust-lang/crates.io-index)",
  "sr-io 0.1.0",
  "sr-primitives 0.1.0",
@@ -1244,7 +1243,7 @@ dependencies = [
  "hash-db 0.9.0 (git+https://github.com/paritytech/trie)",
  "heapsize 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "hex-literal 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "kvdb 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "kvdb 0.1.0 (git+https://github.com/paritytech/parity-common?rev=616b40150ded71f57f650067fcbc5c99d7c343e6)",
  "log 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "parity-codec 2.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "parking_lot 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1792,7 +1791,7 @@ dependencies = [
 "checksum iovec 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "dbe6e417e7d0975db6512b90796e8ce223145ac4e33c377e4a42882a0e88bb08"
 "checksum itoa 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "1306f3464951f30e30d12373d31c79fbd52d236e5e896fd92f96ec7babbbe60b"
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
-"checksum kvdb 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "72ae89206cea31c32014b39d5a454b96135894221610dbfd19cf4d2d044fa546"
+"checksum kvdb 0.1.0 (git+https://github.com/paritytech/parity-common?rev=616b40150ded71f57f650067fcbc5c99d7c343e6)" = "<none>"
 "checksum lazy_static 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "76f033c7ad61445c5b347c7382dd1237847eb1bce590fe50365dcb33d546be73"
 "checksum lazy_static 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ca488b89a5657b0a2ecd45b95609b3e848cf1755da332a0da46e2b2b1cb371a7"
 "checksum lazycell 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ddba4c30a78328befecec92fc94970e53b3ae385827d28620f0f5bb2493081e0"
@@ -1818,7 +1817,7 @@ dependencies = [
 "checksum openssl 0.10.15 (registry+https://github.com/rust-lang/crates.io-index)" = "5e1309181cdcbdb51bc3b6bedb33dfac2a83b3d585033d3f6d9e22e8c1928613"
 "checksum openssl-sys 0.9.39 (registry+https://github.com/rust-lang/crates.io-index)" = "278c1ad40a89aa1e741a1eed089a2f60b18fab8089c3139b542140fc7d674106"
 "checksum owning_ref 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "cdf84f41639e037b484f93433aa3897863b561ed65c6e59c7073d7c561710f37"
-"checksum parity-bytes 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fa5168b4cf41f3835e4bc6ffb32f51bc9365dc50cb351904595b3931d917fd0c"
+"checksum parity-bytes 0.1.0 (git+https://github.com/paritytech/parity-common?rev=616b40150ded71f57f650067fcbc5c99d7c343e6)" = "<none>"
 "checksum parity-codec 2.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "dca389ea5e1632c89b2ce54f7e2b4a8a8c9d278042222a91e0bf95451218cb4c"
 "checksum parity-codec-derive 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ffa42c2cb493b60b12c75b26e8c94cb734af4df4d7f2cc229dc04c1953dac189"
 "checksum parity-wasm 0.31.3 (registry+https://github.com/rust-lang/crates.io-index)" = "511379a8194230c2395d2f5fa627a5a7e108a9f976656ce723ae68fca4097bfc"