Unify the iconview and listview modes into a single responsive grid view
Submitted by Jeff F.T.
Assigned to Jeff F.T.
Pitivi's media library has two view modes to accomodate different types of screens:
Listview is better-suited to smaller resolutions (ex: 1280x*, 1024x*).
We show smaller thumbnails.
Iconview leverages high-res wide screens (ex: 1920x* and bigger) better,
as its items will wrap horizontally.
Iconview has rather annoying bugs and lackluster performance.
Having both iconview and listview/treeview complexifies the code and the user experience.
When possible, we should switch to a "responsive" grid widget in GTK (bug # 704722).
Imported from https://bugzilla.gnome.org/show_bug.cgi?id=708332