fix data_loss_protect (missing return, json conversion)

electrum/lnchannel.py

@@ -153,7 +153,7 @@ class Channel(Logger):
         self.data_loss_protect_remote_pcp[key] = value
 
     def get_data_loss_protect_remote_pcp(self, key):
-        self.data_loss_protect_remote_pcp.get(key)
+        return self.data_loss_protect_remote_pcp.get(key)
 
     def set_remote_update(self, raw):
         self.storage['remote_update'] = raw.hex()

electrum/wallet_db.py

@@ -971,6 +971,8 @@ class WalletDB(JsonDB):
             v = dict((k, {(prevout, value) for (prevout, value) in x}) for k, x in v.items())
         elif key == 'buckets':
             v = dict((k, ShachainElement(bfh(x[0]), int(x[1]))) for k, x in v.items())
+        elif key == 'data_loss_protect_remote_pcp':
+            v = dict((k, bfh(x)) for k, x in v.items())
         return v
 
     def _convert_value(self, path, key, v):