[schema] improve normalization of RQLExpressions
Parse and print back the expression instead of manipulating the string.
Among other benefits, it means we don't mangle embedded string constants
that contain commas or multiple spaces.
Closes #6694426
sync_schema_props_perms('EmailAddress')
for source in rql('CWSource X WHERE X type "ldapuser"').entities():
config = source.dictconfig
host = config.pop('host', u'ldap')
protocol = config.pop('protocol', u'ldap')
source.cw_set(url=u'%s://%s' % (protocol, host))
source.update_config(skip_unknown=True, **config)
commit()