Ignore output switcher chip for color transitions

The output switcher chip intentionally changes colors when toggling dark
mode. Since that element  uses the same accent colors as other elements, we can
ignore changes for it when deciding whether to animate to a new palette

Fixes: 261695345
Test: manual - toggle dark mode, observe chip color changes without any other flickering
Change-Id: I960d4f64f86fced604b18b86ff0aba5724af4abc