Verify GRANDPA justifications from runtime (paritytech#353)

* verify justifications from runtime

* unreachable

modules/substrate/Cargo.toml

@@ -8,16 +8,35 @@ license = "GPL-3.0-or-later WITH Classpath-exception-2.0"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-serde = { version = "1.0", optional = true }
+codec = { package = "parity-scale-codec", version = "1.3.4", default-features = false }
+finality-grandpa = { version = "0.12.3", default-features = false }
 hash-db = { version = "0.15.2", default-features = false }
 
 # Substrate Based Dependencies
+[dependencies.frame-support]
+version = "2.0.0-rc6"
+tag = 'v2.0.0-rc6'
+default-features = false
+git = "https://github.com/paritytech/substrate/"
+
+[dependencies.sp-finality-grandpa]
+version = "2.0.0-rc6"
+tag = 'v2.0.0-rc6'
+default-features = false
+git = "https://github.com/paritytech/substrate/"
+
 [dependencies.sp-runtime]
 version = "2.0.0-rc6"
 tag = 'v2.0.0-rc6'
 default-features = false
 git = "https://github.com/paritytech/substrate/"
 
+[dependencies.sp-std]
+version = "2.0.0-rc6"
+tag = 'v2.0.0-rc6'
+default-features = false
+git = "https://github.com/paritytech/substrate/"
+
 [dependencies.sp-trie]
 version = "2.0.0-rc6"
 tag = 'v2.0.0-rc6'
@@ -30,6 +49,12 @@ tag = 'v2.0.0-rc6'
 default-features = false
 git = "https://github.com/paritytech/substrate/"
 
+[dev-dependencies.sp-keyring]
+version = "2.0.0-rc6"
+tag = 'v2.0.0-rc6'
+default-features = false
+git = "https://github.com/paritytech/substrate/"
+
 [dev-dependencies.sp-state-machine]
 version = "0.8.0-rc6"
 tag = 'v2.0.0-rc6'
@@ -39,7 +64,11 @@ git = "https://github.com/paritytech/substrate/"
 [features]
 default = ["std"]
 std = [
-	"serde",
+	"codec/std",
+	"finality-grandpa/std",
+	"frame-support/std",
+	"sp-finality-grandpa/std",
 	"sp-runtime/std",
+	"sp-std/std",
 	"sp-trie/std",
 ]