more resilient rebuild keyspace graph check, tablet controls not in effect if there has no actual disabled query service
more resilient rebuild keyspace graph check, tablet controls not in effect if there has no actual disabled query service

Signed-off-by: hzhou <14beb26d16282a7dbbca556b477ed4fbc7b7cb81@pinterest.com>

vitessio/vitess,tinyspeck/vitess,mahak/vitess,vitessio/vitess,mahak/vitess,mahak/vitess,mahak/vitess,mahak/vitess,tinyspeck/vitess,vitessio/vitess,tinyspeck/vitess,vitessio/vitess,mahak/vitess,tinyspeck/vitess,vitessio/vitess,mahak/vitess,vitessio/vitess,tinyspeck/vitess,vitessio/vitess,vitessio/vitess,tinyspeck/vitess,mahak/vitess,tinyspeck/vitess