Don't crash if name.txt doesn't exist; this can happen if you try to get name before you open a database

svn: r16666

src/gen/db/read.py

@@ -1604,5 +1604,5 @@ class DbBsddbRead(DbReadBase, Callback):
             name_file.close()
         except (OSError, IOError), msg:
             self.__log_error()
-            raise Errors.DbError(msg)
+            name = None
         return name