Bump wabt to 0.4. (#274)

substrate/substrate/runtime/contract/Cargo.toml

@@ -11,7 +11,7 @@ parity-wasm = { version = "0.30", default_features = false }
 pwasm-utils = { version = "0.2", default_features = false }
 
 [dev-dependencies]
-wabt = "0.1.7"
+wabt = "0.4"
 assert_matches = "1.1"
 
 [features]

substrate/substrate/runtime/staking/Cargo.toml

@@ -23,7 +23,7 @@ substrate-runtime-session = { path = "../session", default_features = false }
 substrate-runtime-timestamp = { path = "../timestamp", default_features = false }
 
 [dev-dependencies]
-wabt = "0.1.7"
+wabt = "0.4"
 
 [features]
 default = ["std"]