Cloud Sync WebDAV Support for Android

[eastcoastcoder]

First and foremost consider this:

• Only RetroArch bugs should be filed here. Not core bugs or game bugs
• This is not a forum or a help section, this is strictly developer oriented

Description

• On iOS/TVOS platforms, an additional setting for Cloud Sync exists
• On Android and possibly other platforms these configuration options are missing
• I play my games on AppleTV and see the save has synced successfully to my WebDAV share, but then have to run another program (Folder Sync) manually on my Android phone to keep these saves synced up to my share.
• Ideally both platforms could have this functionality built in.

Expected behavior

• I would expect interfacing with a WebDAV share would work fairly similarly. However I'm unaware of the potential challenges to port this to other platforms. (Though I did read a more generic bounty issue for some universal cloud support earlier)

Actual behavior

• Options do not exist on Android, as well as potentially other platforms.

Steps to reproduce the bug

1. Go to Settings
2. Go to Saving
3. See that Cloud Sync is not at the end of the list (It would be on AppleTV)

Bisect Results

• Feature just missing

Version/Commit

• RetroArch: 1.19.1

Environment information

• OS: Android

[eastcoastcoder]

In addition to what I've stated above, my Apple TV's last modified date for all save/savestate files is +4 hours from Eastern even though my phone and ATV are configured the same (is this UTC possibly?)

So my third party app (FolderSync) cannot properly identify which file is newer. As a result, I am one save behind or 4 hours delayed before syncing correctly. To be honest, the easiest approach is to just cut out the middleman however I'm curious if there is a underlying timing issue on ATV or a configuration issue on my end...

Screenshot attached of my ATV save synced down, and my local Android save now taking an "older" yet true, modified date due to this discrepancy.