* This especially helps when you switch between insert/gallery and have non-images selected (as galleries don't support non-images).
* The views now act as filters on the "master" selection, instead of having their own selections that get passed around.
git-svn-id: https://develop.svn.wordpress.org/trunk@23089 602fd350-edb4-49c9-b593-d223f7449a82