switch: focus indicator is wrong on dark themes

[devversion]

Seems like the focus indicator is not correct on dark themes.

• It should be white on dark themes with an opacity of 12%
• It should be black on light themes with an opacity of 12% as well.

FYI: Actually the ripple indicator is correct on dark themes. But not the focus indicator for keyboard interaction.

[EladBezalel]

Actually the colors of the switch aren't matching the specs in dark/light themes

''	Light	Dark
Thumb On	Swatch 500, Opacity 100%	Swatch 200, Opacity 100%
Track On	Swatch 500, Opacity 50%	Swatch 200, Opacity 50%
Thumb Off	Grey 50, #FAFAFA, Opacity 100%	Grey 400, #BDBDBD, Opacity 100%
Track Off	#000000, Opacity 38%	#FFFFFF, Opacity 30%
Thumb Disabled	Grey 400, #BDBDBD, Opacity 100%	Grey 800, #424242, Opacity 100%
Track Disabled	#000000, Opacity 12%	#FFFFFF, Opacity 10%

Currently we can't distinguish between dark and light themes in our theming system