cleanup json crate (#11027)

* [json]: cleanup

write something here....

* nit: commit new/moved files

* nit: remove needless features

* nits

* fix(grumbles): use explicit import `DifficultyTest`

* fix(grumbles): remove needless type hints

* fix(grumble): docs `from -> used by`

Co-Authored-By: David <dvdplm@gmail.com>

* fix(grumbles): use explicit `imports`

* fix(grumble): merge `tx` and `tx_with_signing_info`

* fix(grumbles): resolve introduced `TODO's`

rpc/src/v1/tests/eth.rs

@@ -15,8 +15,8 @@
 // along with Parity Ethereum.  If not, see <http://www.gnu.org/licenses/>.
 
 //! rpc integration tests.
-use std::env;
-use std::sync::Arc;
+
+use std::{env, sync::Arc};
 
 use accounts::AccountProvider;
 use client_traits::{BlockChainClient, ChainInfo, ImportBlock};
@@ -26,7 +26,7 @@ use spec::{Genesis, Spec, self};
 use ethcore::test_helpers;
 use verification::VerifierType;
 use ethereum_types::{Address, H256, U256};
-use ethjson::blockchain::BlockChain;
+use ethjson::test_helpers::blockchain::BlockChain;
 use ethjson::spec::ForkSpec;
 use io::IoChannel;
 use miner::external::ExternalMiner;
@@ -85,7 +85,7 @@ struct EthTester {
 impl EthTester {
 	fn from_chain(chain: &BlockChain) -> Self {
 
-		let tester = if ::ethjson::blockchain::Engine::NoProof == chain.engine {
+		let tester = if ethjson::test_helpers::blockchain::Engine::NoProof == chain.engine {
 			let mut config = ClientConfig::default();
 			config.verifier_type = VerifierType::CanonNoSeal;
 			config.check_seal = false;

rpc/src/v1/tests/mod.rs

@@ -32,7 +32,7 @@ macro_rules! extract_chain {
 	(iter $file:expr) => {{
 		const RAW_DATA: &'static [u8] =
 			include_bytes!(concat!("../../../../ethcore/res/ethereum/tests/", $file, ".json"));
-		::ethjson::blockchain::Test::load(RAW_DATA).unwrap().into_iter()
+		ethjson::test_helpers::blockchain::Test::load(RAW_DATA).unwrap().into_iter()
 	}};
 
 	($file:expr) => {{