We were assuming that setting stock-size would affect the emblems in
GEmblemedIcons, but not the icons themselves. This is a bit weird.
GtkCellRendererPixbuf:gicon is meant to work with
GtkCellRendererPixbuf:stock-size, and this was only working so far
because GTK_ICON_LOOKUP_FORCE_SIZE was not being used when loading
the icon.
Let's composite the emblems ourselves so that we don't have to depend
on this quirky interpretation of stock-size.
Unfortunately, we can not directly use the pixbufs because they are
unaware of the scale factor and GTK+ will scale them on HiDpi
displays. Since our pixbufs already have enough pixels to work well
with such devices, scaling them further will lead to giant, fuzzy
thumbnails. Hence, we use GtkCellRendererPixbuf:surface with the
scale factor codified in it.
https://bugzilla.gnome.org/show_bug.cgi?id=732375
When using a small screen, make sure that the whole of the dialogue
is visible, including the confirmation buttons. This means that the
dialogue will be maximised when on smaller screens (just like its
parent), and that we won't set a number of columns for the icon
view.
We will also stop making the dialogue much bigger than the
Settings window itself.
https://bugzilla.gnome.org/show_bug.cgi?id=692495
Instead of setting the size on each child, set it on the parent grid
because only one of those children are visible at any given point.
We are cheating a bit by ignoring the fact there is a second child
which is always shown -- the button box. This will make the other
children lose some height and the dialog will be smaller. However it is
still too big for smaller screens.
https://bugzilla.gnome.org/show_bug.cgi?id=708943
Show a message to the user when the Pictures source is empty, inspired both
in design and widget layout by the EmptyResultsBox from gnome-documents.
https://bugzilla.gnome.org/show_bug.cgi?id=630892
