gtk_fb: WIP switch to using GtkDrawingArea

I still need to dig into which is preferable from a performance
perspective, but the existing GtkImage integration with setting
its cairo surface for the page flip seems to cause lots of
size-allocations and errors on wayland as-is.

Note this also bumps the rototiller submodule to a different branch
for til_fb_context().

1 files changed, 0 insertions, 0 deletions

diff --git a/rototiller b/rototiller
-Subproject 4351afc62b3dd1c7fb7f0bc563dae22ee0ec73d
+Subproject 2c01f07385db88fa92f3a3789457c68db0d7d49