Implement AppInvite and Firebase DynamicLinks

[alexandruchircu]

Some apps complain and some apps crash because of missing AppInvite/DynamicLinks.

Pull requests incoming on GmsApi, GmsLib, GmsCore.

[arnauvp]

@mar-v-in @ale5000-git @benwaffle we found these fixes prevented a few apps from crashing.
Do you need anything else in order to get them integrated? If you can no longer afford maintaining these projects, we (the e.foundation) wouldn't mind giving a hand until you have more time to come back to it.

[sam-public]

@mar-v-in Any progress on merging these changes? Multiple apps are breaking with firebase.

[mar-v-in]

@alexandruchircu @arnauvp can you point to some apps affected by this for testing please?

[dicer]

mobile.santander.de.smartsign crashes on startup for me. *Without* the pull request applied! Haven't tested with it

[alexandruchircu]

fr.doctolib.www is the app that led to this being implemented.

[dicer]

@mar-v-in Could we get this merged please? Just stumbled upon it again in one of my apps (can't share the usecase unfortunately, cause it contains private data in the link etc).

[mar-v-in]

This is essentially implemented.
Feel free to send email to microg at larma.de if you don't want to make your issue public for privacy reasons.

[dicer]

Yeah, sorry, just realized that 2 of the 3 merge requests were merged and I see the appropriate debug messages in the log. Will analyze further and get back to you directly.