[mythtv-theming] disabled state for buttonlist?

[Joey Morris]

Buttonlist widgets don't appear to support a disabled state. Is that correct?

This comes up in the new schedule editor screen support introduced in 0.26
(https://code.mythtv.org/trac/changeset/d418754/mythtv). Before, the main
schedule editor screen contained the rule type selector (do not record, record
all, etc.) followed by a series of buttons. When the rule type is "Do not
record", several of the buttons are disabled. Because button widgets do support
a disabled state, the disabled buttons can be themed differently to distinguish
them from the enabled buttons.

Now, however, we can add options directly to that main screen instead of just
buttons. The options are represented by buttonlist widgets. Like the buttons,
some of the options are disabled when the rule type is "Do not record". Unlike
the buttons, it doesn't look like I can theme the enabled and disabled options
differently.