Reloading Edit Service Instance page results in an exception

[irfanhabib]

Steps to reproduce:

1. Create a service instance
2. Go to the Services Wall -> Edit
3. Reload page

Exception is:

core.js:1598 ERROR TypeError: Cannot read property 'guid' of undefined
    at TapSubscriber._tapNext (add-service-instance.component.ts:179)
    at TapSubscriber.push../node_modules/rxjs/_esm5/internal/operators/tap.js.TapSubscriber._next (tap.js:92)
    at TapSubscriber.push../node_modules/rxjs/_esm5/internal/Subscriber.js.Subscriber.next (Subscriber.js:93)
    at FilterSubscriber.push../node_modules/rxjs/_esm5/internal/operators/filter.js.FilterSubscriber._next (filter.js:85)
    at FilterSubscriber.push../node_modules/rxjs/_esm5/internal/Subscriber.js.Subscriber.next (Subscriber.js:93)
    at RefCountSubscriber.push../node_modules/rxjs/_esm5/internal/Subscriber.js.Subscriber._next (Subscriber.js:129)
    at RefCountSubscriber.push../node_modules/rxjs/_esm5/internal/Subscriber.js.Subscriber.next (Subscriber.js:93)
    at ReplaySubject.push../node_modules/rxjs/_esm5/internal/Subject.js.Subject.next (Subject.js:53)
    at ReplaySubject.push../node_modules/rxjs/_esm5/internal/ReplaySubject.js.ReplaySubject.nextInfiniteTimeWindow (ReplaySubject.js:44)
    at ConnectableSubscriber.push../node_modules/rxjs/_esm5/internal/Subscriber.js.Subscriber._next (Subscriber.js:129)

[nwmac]

Fixed.