Add information about old theme to 'theme_switched' action
|Reported by:||evansolomon||Owned by:|
Currently the 'theme_switch' action passes data about the theme you're switching to, but not the theme you're switching from. Adding it there would make it easier to juggle functionality that needs to know about new and old themes. Right now some of this happens by setting an option ('theme_switched') and checking for it on init, then deleting the option. That could be simplified by just passing the old theme's data in theme_switched.
There's an added benefit that we avoid checking for an option on every single request that usually won't be there.