Add option to drag drag/rearrange favorites via NTP

[anthonypkeane]

Description:

Lets figure out a way to drag drag/rearrange favorites

Review

why can’t we drag/rearrange favorites on the home page in the order we like?…

[iccub]

you can do it from the overlay screen cc @kylehickinson

[kylehickinson]

Yeah the reason why we dont allow rearranging on the main NTP is because you aren't able to see all your favourites like you can once you focus the URL bar. We could perhaps enable rearranging on the NTP but you'd only be able to drag & drop between your top 4

[iccub]

Requirements:
Allow user to rearrange the visible favorites on NTP. Favorites outside of visible ones do not need to be handled.

[srirambv]

Blocked on #4463

[kjozwiak]

Labelling this one as Verified/Passed as verifications were completed via #4463 (comment). The only remaining issue is #4651 on iOS 14 which will be QA'd in that particular GH issue. As per #4651 (comment), we're reverting the change for iOS 14 so you can't move the NTP tiles around.