A better theme enum?

[ms-somanna]

Right now there is a an enum with light and dark values: Themes.Light and Themes.Dark And for switching to system theme we need to set IsUsingSystemTheme = true.

How about having a enum to include the system theme:

Themes.Light, Themes.Dark, Themes.System and Themes.SystemWithDefaultAccentColor

When Themes.System is selected the background color scheme and accent color follows the system theme. This the same as setting IsUsingSystemTheme = True.

And, When Themes.SystemWithDefaultAccent is selected the background color scheme follows the system theme. But the Accent color remains default. This the same as setting

IsUsingSystemTheme =  True
AccentBrush = null