only use engineclient trait for engines, separated from client trait

ethcore/src/client/traits.rs

@@ -307,7 +307,7 @@ pub trait MiningBlockChainClient: BlockChainClient {
 }
 
 /// Client facilities used by internally sealing Engines.
-pub trait EngineClient: MiningBlockChainClient {
+pub trait EngineClient: Sync + Send {
 	/// Make a new block and seal it.
 	fn update_sealing(&self);
 
@@ -323,6 +323,17 @@ pub trait EngineClient: MiningBlockChainClient {
 	///
 	/// The block corresponding the the parent hash must be stored already.
 	fn epoch_transition_for(&self, parent_hash: H256) -> Option<::engines::EpochTransition>;
+
+	/// Get block chain info.
+	fn chain_info(&self) -> BlockChainInfo;
+
+	/// Like `call`, but with various defaults. Designed to be used for calling contracts.
+	fn call_contract(&self, id: BlockId, address: Address, data: Bytes) -> Result<Bytes, String>;
+
+	/// Import a transaction: used for misbehaviour reporting.
+	fn transact_contract(&self, address: Address, data: Bytes) -> Result<TransactionImportResult, EthcoreError>;
+
+	fn block_number(&self, id: BlockId) -> Option<BlockNumber>;
 }
 
 /// Extended client interface for providing proofs of the state.