Use power/reset/exit icons from theme if .svg are unavailable

[NHOrus]

Due to packaging issues, nwg-drawer in gentoo shows no power/reset/exit/sleep icons.
It would be nice, if svg icons are missing, to pull icon from theme. It also would unify looks of apps and buttons.

[nwg-piotr]

Which specific icon names would you like me to use? Remember, that they must exist in Adwaita icon theme.

[NHOrus]

Exit - system-log-out-symbolic.svg
Lock - system-lock-screen-symbolic.svg
Poweroff - system-shutdown-symbolic.svg
Reboot - system-reboot-symbolic.svg
Can't find any for Sleep

[nwg-piotr]

Can't find any for Sleep

Don't stop searching! ;)

[nwg-piotr]

Maybe this one?

[nwg-piotr]

Finally I ended up using the face-yawn-symbolic icon, as the above looks differently in themes other than Adwaita (exclamation, mostly). Keep in mind that it still won't look well with some icon themes.

To use icon theme icons, add the -pbuseicontheme flag.

[NHOrus]

Thank you