[test/fix] prevent FirefoxHelper from silently failing to start
This was breaking some tests without any obvious error message and you should
fail as early as possible to make debugging easier.
Closes #17260390
import ConfigParser
try:
undo_actions = config.cfgfile_parser.get('MAIN', 'undo-support', False)
except ConfigParser.NoOptionError:
pass # this conf. file was probably already migrated
else:
config.global_set_option('undo-enabled', bool(undo_actions))