Comment 6 for bug 1559731

This looks like a Desktop variation of bug #1388235. The solution there was to provide extra icons for 10%, 30%, 50%, 70%, and 90% so that we could improve our accuracy when rounding to the closest icon, and also to special case the rounding between [20-30%) to avoid hitting the red-at-20% icons from not just our own icon sets but others eg Humanity.

I'm seeing the same behavior on my Xenial box when I set the battery to 28%. The icon list sent by indicator-power is correct:

> {"battery-030", "gpm-battery-030", "battery-020", "gpm-battery-020", "battery-low-symbolic", "battery-low"}

So the rounding rules described in bullet point #2 of https://bugs.launchpad.net/ubuntu/+source/indicator-power/+bug/1388235/comments/5 are working correctly and things look great on devices with suru icons. The problem for the Desktop is that bullet point #3 is incorrect:

> indicator-power keep providing the current icon names as fallbacks so that this fix doesn't break compatibility with other icon themes

Because ?keeping the current icon names as fallbacks" means the problem still persists in other icon sets. We should tweak the special case rule for [20-30%) s.t. the fallback icon is *040* instead of *020*, e.g.:

- {"battery-030", "gpm-battery-030", "battery-020", "gpm-battery-020", "battery-low-symbolic", "battery-low"}
+ {"battery-030", "gpm-battery-030", "battery-040", "gpm-battery-040", "battery-low-symbolic", "battery-low"}