Deprecate AppChooser, AppChooserButton, AppChooserDialog,
AppChooserWidget, CellArea, CellAreaBox, CellAreaContext,
CellLayout, CellRenderer, CellRendererAccel, CellRendererCombo,
CellRendererPixbuf, CellRendererProgress, CellRendererSpin,
CellRendererSpinner, CellRendererText, CellRendererToggle, CellView,
ComboBox, ComboBoxText, EntryCompletion, IconView, ListStore,
ListViewText, StyleContext, TreeDragDest, TreeDragSource,
TreeIter and other classes in treeiter.hg,
TreeModel, TreeModelFilter, TreeModelSort, TreePath, TreeRowReference,
TreeSelection, TreeSortable, TreeStore, TreeView, TreeViewColumn,
namespace CellRenderer_Generation, namespace TreeView_Private

The corresponding API in GTK has been deprecated.

Demo programs still use deprecated API. It's not possible to build
the demo programs with build-deprecated-api=false.