wallet.get_tx_parents: explicitly handle missing "from address"

(happened to work even without this)

electrum/address_synchronizer.py

@@ -787,7 +787,7 @@ class AddressSynchronizer(Logger, EventListener):
         self.db.add_num_inputs_to_tx(txid, len(tx.inputs()))
         return fee
 
-    def get_addr_io(self, address):
+    def get_addr_io(self, address: str):
         with self.lock, self.transaction_lock:
             h = self.get_address_history(address).items()
             received = {}

electrum/wallet.py

@@ -922,6 +922,8 @@ class Abstract_Wallet(ABC, Logger, EventListener):
                 parents.append(_txid)
                 # detect address reuse
                 addr = self.adb.get_txin_address(txin)
+                if addr is None:
+                    continue
                 received, sent = self.adb.get_addr_io(addr)
                 if len(sent) > 1:
                     my_txid, my_height, my_pos = sent[txin.prevout.to_str()]