wallet_db: migrate to upfront shutdown scripts

electrum/wallet_db.py

@@ -52,7 +52,7 @@ if TYPE_CHECKING:
 
 OLD_SEED_VERSION = 4        # electrum versions < 2.0
 NEW_SEED_VERSION = 11       # electrum versions >= 2.0
-FINAL_SEED_VERSION = 33     # electrum >= 2.7 will set this to prevent
+FINAL_SEED_VERSION = 34     # electrum >= 2.7 will set this to prevent
                             # old versions from overwriting new format
 
 
@@ -181,6 +181,7 @@ class WalletDB(JsonDB):
         self._convert_version_31()
         self._convert_version_32()
         self._convert_version_33()
+        self._convert_version_34()
         self.put('seed_version', FINAL_SEED_VERSION)  # just to be sure
 
         self._after_upgrade_tasks()
@@ -710,6 +711,18 @@ class WalletDB(JsonDB):
 
         self.data['seed_version'] = 33
 
+    def _convert_version_34(self):
+        if not self._is_upgrade_method_needed(33, 33):
+            return
+
+        channels = self.data.get('channels', {})
+        for key, item in channels.items():
+            item['local_config']['upfront_shutdown_script'] = \
+                item['local_config'].get('upfront_shutdown_script') or ""
+            item['remote_config']['upfront_shutdown_script'] = \
+                item['remote_config'].get('upfront_shutdown_script') or ""
+        self.data['seed_version'] = 34
+
     def _convert_imported(self):
         if not self._is_upgrade_method_needed(0, 13):
             return