Background color problem with Gtk+ 3.6

[Mark Leisher <mleisher gmail com>]

The background color returned by 
gtk_style_context_get_background_color() is always {0.0,0.0,0.0,0.0}. 
This is with a fresh install of the latest Gtk+ packages, no 
customizations, and a custom widget.

I've tested 3.6.1 through 3.6.4, all exhibit the same behavior. I must 
be missing a style context or GDK cairo call somewhere. I checked the 
widget sources in Gtk+ 3.6.4 and don't see anything missing from my own 
code, but I may not have looked carefully enough.
--
Mark Leisher