Rework the way we create "stock" icons for Pitivi-specific icons - migrate to GtkIconTheme
@jeff
Submitted by Jeff F.T. Assigned to Alex Băluț @aleb
Description
If you look at the "createStockIcons" method in mainwindow.py, you can see that we have code that takes our custom icons for pitivi-specific actions and turns them into "stock" icons to be used anywhere in Pitivi (ex: in the selection_actions and playhead_actions in the _createActions method in timeline/timeline.py)
This approach goes back to time immemorial.
I was warned that this won't fly much longer, as stock icons are being deprecated in GTK 3.10+. I had this memo from a discussion in January 2014:
<Company>
nekohayo: use the icon theme
<nekohayo>
so now the installer/packaging needs to register every pitivi action icon into the icon theme?
<Company>
yes
<nekohayo>
ah with GtkIconFactory still (I hope)? and GtkIconSet
<Company>
not GtkIconFactory
Official deprecation notices:
https://developer.gnome.org/gtk3/stable/gtk3-Themeable-Stock-Images.html#gtk-icon-set-new-from-pixbuf
https://developer.gnome.org/gtk3/stable/gtk3-Themeable-Stock-Images.html#GtkIconFactory-struct (all of those GtkIconFactory methods point to GtkIconTheme instead)
I don't really know what to do with this at this point code-wise (hoping that some smart eyes see this bug report :), this might mean some changes in how we do packaging too.
Imported from https://bugzilla.gnome.org/show_bug.cgi?id=737553