According to the following this is not supported:
* http://stackoverflow.com/a/13471695/2391921
This uses the approach in that SO answer, by extracting the attribute to
instead point at a drawable, and have one drawable for each theme.
Fixes#979.
* Replace hardcoded color values with references to style.xml,
which in turn has different values for light and dark theme.
* Force reload the activity to get the theme applied.
TODO:
* Swap uses it's own theme, need to figure out a way to
handle that. Currently the main Nearby screen which you get
to from the bottom navigation is ok, but anything after
that is light / custom themed.
