Use basic scroll indicators when a dialog shows a list.
Mostly for material guidelines. Excluded dialogs and int pref dialog
have not been modified, as I am still working on revamping those.
Add support for file size, format, and parent directory values to the
MediaStore backend.
I hope that this handles API boundaries properly, especially regarding
path parsing. As a side-note, I have learned of a way to extend
external volume support to even earlier versions. Maybe.
