never include android-xml icons into an f-droid repo
Preliminary conclusion: Xml icons can't be used without the whole app, and converting them is way too complicated for us.
So let's just make sure they're not shipped in the repo and instead fix fdroidclient#1460 (closed)
Every fdroid repo provides direct download links for the app icons at the various DPI densities that Android supports. Now there is a vector XML format for Android icons, and fdroid should support it. It can be extracted from the APK just like the PNGs, there just needs to be a standard fdroid/repo/icons-anydpi folder (or perhaps another name makes sense) to hold them.
Then there needs to be a way to communicate that an XML file is available. Perhaps the existing
icon field in the index can be reused, just use the existing naming scheme, but ending with
.xml instead of
.png. Then if fdroidclient is running on an older platform, it can just try replacing
.png for the icon.
This is more necessary since apps with min SDK of 21 can work with only XML icons, i.e. omit the PNGs. For example: