removed engine retrieval from client public api

ethcore/src/client/client.rs

@@ -430,10 +430,6 @@ impl<V> BlockChainClient for Client<V> where V: Verifier {
 		block.try_seal(self.engine.deref().deref(), seal)
 	}
 
-	fn engine(&self) -> &Engine {
-		self.engine.deref().deref()
-	}
-
 	// TODO [todr] Should be moved to miner crate eventually.
 	fn prepare_sealing(&self, author: Address, gas_floor_target: U256, extra_data: Bytes, transactions: Vec<SignedTransaction>)
 		-> (Option<ClosedBlock>, HashSet<H256>) {

ethcore/src/client/mod.rs

@@ -134,12 +134,6 @@ pub trait BlockChainClient : Sync + Send {
 	/// Makes a non-persistent transaction call.
 	fn call(&self, t: &SignedTransaction) -> Result<Executed, ExecutionError>;
 
-	/// Attempt to seal the block internally. See `Engine`.
-	fn generate_seal(&self, block: &ExecutedBlock, accounts: Option<&AccountProvider>) -> Option<Vec<Bytes>> { self.engine().generate_seal(block, accounts) }
-
-	/// Executes a function providing it with a reference to an engine.
-	fn engine(&self) -> &Engine;
-
 	/// Returns traces matching given filter.
 	fn filter_traces(&self, filter: TraceFilter) -> Option<Vec<LocalizedTrace>>;
 

ethcore/src/client/test_client.rs

@@ -430,10 +430,6 @@ impl BlockChainClient for TestBlockChainClient {
 		}
 	}
 
-	fn engine(&self) -> &Engine {
-		unimplemented!();
-	}
-
 	fn filter_traces(&self, _filter: TraceFilter) -> Option<Vec<LocalizedTrace>> {
 		unimplemented!();
 	}