More follow-up to 37c4ef5

Paranoia: invalidate the common sighash cache if the call path passes
through deserialize() successfully (deserialize usually short circuit
aborts if it's a redundant deserialization but if it proceeds we should
definitely invalitate the cache if it exists).

lib/transaction.py

@@ -517,6 +517,7 @@ def deserialize(self):
         if self._inputs is not None:
             return
         d = deserialize(self.raw)
+        self.invalidate_common_sighash_cache()
         self._inputs = d['inputs']
         self._outputs = [(x['type'], x['address'], x['value']) for x in d['outputs']]
         assert all(isinstance(output[1], (PublicKey, Address, ScriptOutput))