Fix panic on importing own invalid transaction (#3550)

ethcore/src/miner/miner.rs

@@ -580,15 +580,13 @@ impl Miner {
 		let gas_required = |tx: &SignedTransaction| tx.gas_required(&schedule).into();
 		let best_block_header: Header = ::rlp::decode(&chain.best_block_header());
 		transactions.into_iter()
-			.filter(|tx| match self.engine.verify_transaction_basic(tx, &best_block_header) {
-					Ok(()) => true,
+			.map(|tx| {
+				match self.engine.verify_transaction_basic(&tx, &best_block_header) {
 					Err(e) => {
 						debug!(target: "miner", "Rejected tx {:?} with invalid signature: {:?}", tx.hash(), e);
-						false
-					}
-				}
-			)
-			.map(|tx| {
+						Err(e)
+					},
+					Ok(()) => {
 						let origin = accounts.as_ref().and_then(|accounts| {
 							tx.sender().ok().and_then(|sender| match accounts.contains(&sender) {
 								true => Some(TransactionOrigin::Local),
@@ -604,6 +602,8 @@ impl Miner {
 								transaction_queue.add_with_banlist(tx, &fetch_account, &gas_required)
 							}
 						}
+					},
+				}
 			})
 			.collect()
 	}