[gtk] Non-fast-forward update to branch BUG_gtk3_containers_scroll_precedence

[Nelson Ben <nbenitez src gnome org>]

The branch 'BUG_gtk3_containers_scroll_precedence' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  a1628cb... containers that can be scrolled should have precedence

Commits added to the branch:

  7f7c6b8... scrolling a container should not scroll child widgets