Migrate ChatFragment to ViewPager2

[TacoTheDank]

Brought over from #152

Separated into two PRs to prevent holdup of perfectly good activity viewpager2s.

[TacoTheDank]

@samfundev I have an idea about how to solve this. Instead of using position numbers manually, what about using an array that sets the number of tabs automatically (depending on whether subscriber emotes are enabled or not)? Like this.

I actually tried and got to a good point, but then I got crashes.

[TacoTheDank]

@samfundev I think I have successfully fixed the issue with the tabs. Here's an APK to test. app-debug.zip

The only bug left now I think is the scroll-jumping that I mentioned in the other PR.

EDIT: Nevermind, fuck.

Ok, well, the tablayout and viewpager themselves work fine, but the mood icon still does what I said in the other PR.

[RickyM7]

I tested the Debug Build and everything seemed to work perfectly (I at least didn't see any bugs, however I tested it without logging in).

• Device: Redmi Note 4 (MIUI 11 - Android 7.0)

[TacoTheDank]

@RickyM7 I'm pretty sure you'll have to log in to test it, as the chatting feature (not to be mistaken with the chat itself) does not appear if you are not logged in. It's a little bit of a hassle (having to input the 2FA code from your email and whatnot), but I have to do it whenever I'm testing as well lol

Also the APK is now outdated, so I'll have to fix it

[RickyM7]

@TacoTheDank Got it! When the Apk is updated I will test correctly.