Fix issue that prevented new contacts from being saved

[hanzi]

Whenever I would compile the JavaScript sources myself, I would run into an issue when creating a new contact:

1. I would create a new contact and fill out some of its fields.
2. The contact wouldn't save, the exclamation mark icon would just stay. If I reload the page at this point, the new contact is gone.
3. If I then selected another contact and returned to the new one, all my previous changes were gone. But if I filled out some fields now, the contact finally got saved.

I can't reproduce this bug with the released version -- though it would still happen if I compiled the JavaScript from the v3.1.7, v3.1.6 or v3.1.5 tags myself. So I'm not sure whether this might be an issue with some dependency or I'm just doing something wrong.

Anyway, the issue as far as I could tell is that the contact watcher of the ContactDetails component fires twice when a new contact is added: once with the new contact and once with the old one. This eventually leads to localContact being overwritten with the old one, so that all save actions actually just save the old contact.

This PR fixes this behaviour by adding a check whether the new contact (inside the watcher) is actually different from the old one. I don't really like this fix because it only attacks the symptom and I still don't have any idea why the watcher is fired twice to begin with.

But at least this way the app is usable again for me.

[codecov]

Codecov Report

Merging #1416 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1416   +/-   ##
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  Coverage   62.31%   62.31%           
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  Files           4        4           
  Lines          69       69           
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  Hits           43       43           
  Misses         26       26

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[skjnldsv]

In any case, this doesn't hurt :)

[DBJRdev]

We encounter the same issue as hanzi wrote, but for us it only began when updating to Contacts 3.1.8 from the GUI within Nextcloud 17.0.2 - no compiling or building anything ourselves. It actually appeared in three of our deployments, all managed servers and one shared hosting at the provider Hetzner.

[hanzi]

@DBJRdev That's odd -- this fix is already included in 3.1.8 and I don't have this issue anymore with Contacts 3.1.8 on Nextcloud 17.0.3.

Could you open a new issue with some more details (including the browser log)?

[DBJRdev]

@hanzi Did as you requested: #1452

[skjnldsv]

Hey!
So this is actually the issue that created #1453

Because on the first save to server, we do not update the real full contact anymore.

The selectContact method also include a proper update of the localContact
All the changes are queued when editing a contact to avoid conflict. The first contact sent init the contact.dav property which is the dav library method object. Because we do not update the contact after the first sync anymore, the localContact used never have the ðav object, and therefore trigger a new vcard creation every time.

Fix incoming