simplify management of list and grid views and keep only one kind
Summary:
Factor all list views into a single one to decrease duplicated code.
fix display of single album list view
we now have a list and a grid generic view
DataListView is the new generic list view
Next one will be the file manager view.
Test Plan: tests are OK and manual testing shows no regressions.
Reviewers: Elisa, ngraham
Reviewed By: Elisa, ngraham
Subscribers: ngraham
Differential Revision: https://phabricator.kde.org/D21774