CW-719 Transaction dates shows incorrectly (#1685)

* ignore 0 height

* fix date format

cw_bitcoin/lib/electrum_transaction_history.dart

@@ -76,8 +76,13 @@ abstract class ElectrumTransactionHistoryBase
         final val = entry.value;
 
         if (val is Map<String, dynamic>) {
-          final tx = ElectrumTransactionInfo.fromJson(val, walletInfo.type);
-          _update(tx);
+          // removing transactions with invalid date
+          if (val['date'] == 1168650000) {
+            transactions.remove(entry.key);
+          } else {
+            final tx = ElectrumTransactionInfo.fromJson(val, walletInfo.type);
+            _update(tx);
+          }
         }
       });
 

cw_bitcoin/lib/electrum_wallet.dart

@@ -1613,7 +1613,7 @@ abstract class ElectrumWalletBase
     }
 
     if (height != null) {
-      if (time == null) {
+      if (time == null && height > 0) {
         time = (getDateByBitcoinHeight(height).millisecondsSinceEpoch / 1000).round();
       }