Deduplicate registrar contract & calling logic (#11110)

* Rename RegistryInfo -> RegistryInfoDeprecated

* Add BlockId parameter to Registrar::get_address and RegistrarClient::call_contract

* Remove RegistrarClient::Call (use async for now); add RegistrarClient::get_address

* Remove Registrar type in favour of naked trait

* Use CallContract trait bound instead of separate call_contract method

* Make RegistrarClient::get_address and URLHint::resolve synchronous

* RegistrarClient::get_address: return check if address is zero

* Modify RegistryInfo::registry_address to take &str

* return Result from RegistryInfo::registry_address

* Replace RegistryInfo with RegistrarClient

- Modifed RegistrarClient::registrar_address to return Option
- Removed BlockChainClient::registrar_address

* Fix other build configs

* Fix unit test builds

* Remove local RegistrarClient type from run::execute_impl

* Remove registrar.json from ethcore

* Formatting/line breaks

* Update RegistrarClient docs, remove explicit lifetime

* Weak ref to ethcore client from hash fetch client

* Fix unit tests

ethcore/src/test_helpers/test_client.rs

@@ -63,7 +63,8 @@ use types::{
 use vm::{Schedule, LastHashes};
 
 use block::{OpenBlock, SealedBlock, ClosedBlock};
-use call_contract::{CallContract, RegistryInfo};
+use call_contract::CallContract;
+use registrar::RegistrarClient;
 use client::{
 	ReopenBlock, PrepareOpenBlock, ImportSealedBlock, BroadcastProposalBlock, Call,
 	EngineInfo, BlockProducer, SealedBlockImporter,
@@ -532,7 +533,20 @@ impl BlockInfo for TestBlockChainClient {
 }
 
 impl CallContract for TestBlockChainClient {
-	fn call_contract(&self, _id: BlockId, _address: Address, _data: Bytes) -> Result<Bytes, String> { Ok(vec![]) }
+	fn call_contract(
+		&self,
+		_block_id: BlockId,
+		_address: Address,
+		_data: Bytes
+	) -> Result<Bytes, String> {
+		Ok(vec![])
+	}
+}
+
+impl RegistrarClient for TestBlockChainClient {
+	fn registrar_address(&self) -> Option<Address> {
+		None
+	}
 }
 
 impl TransactionInfo for TestBlockChainClient {
@@ -543,10 +557,6 @@ impl TransactionInfo for TestBlockChainClient {
 
 impl BlockChain for TestBlockChainClient {}
 
-impl RegistryInfo for TestBlockChainClient {
-	fn registry_address(&self, _name: String, _block: BlockId) -> Option<Address> { None }
-}
-
 impl ImportBlock for TestBlockChainClient {
 	fn import_block(&self, unverified: Unverified) -> EthcoreResult<H256> {
 		let header = unverified.header;
@@ -916,8 +926,6 @@ impl BlockChainClient for TestBlockChainClient {
 		let signed = SignedTransaction::new(transaction.with_signature(sig, chain_id)).unwrap();
 		self.miner.import_own_transaction(self, signed.into())
 	}
-
-	fn registrar_address(&self) -> Option<Address> { None }
 }
 
 impl IoClient for TestBlockChainClient {