fixup! Implement upgrade procedure to migrate to the new torrent store.

Tribler/Core/Upgrade/db_upgrader.py

@@ -39,11 +39,12 @@ class DBUpgrader(object):
     structure from Tribler version 6.3 to 6.4.
     """
 
-    def __init__(self, session, db, status_update_func=None):
+    def __init__(self, session, db, torrent_store, status_update_func=None):
         self._logger = logging.getLogger(self.__class__.__name__)
         self.session = session
         self.db = db
         self.status_update_func = status_update_func if status_update_func else lambda _: None
+        self.torrent_store = torrent_store
 
         self.failed = True
         self.torrent_collecting_dir = self.session.get_torrent_collecting_dir()
@@ -357,13 +358,10 @@ def reimport_torrents(self):
         torrent_db_handler.misc_db.initialize()
         torrent_db_handler.category = Category.getInstance()
 
-        self.status_update_func("Opening torrent store...")
-        torrent_store = TorrentStore(self.session.get_torrent_store_dir())
-
         # TODO(emilon): It would be nice to drop the corrupted torrent data from the store as a bonus.
         self.status_update_func("Registering recovered torrents...")
         try:
-            for infoshash_str, torrent_data in torrent_store.itervalues():
+            for infoshash_str, torrent_data in self.torrent_store.itervalues():
                 self.status_update_func("> %s" % infoshash_str)
                 torrentdef = TorrentDef.load_from_memory(torrent_data)
                 if torrentdef.is_finalized():
@@ -375,4 +373,4 @@ def reimport_torrents(self):
             torrent_db_handler.close()
             Category.delInstance()
             self.db.commit_now()
-            return torrent_store.close()
+            return self.torrent_store.flush()