menu: Respect borders properly for scroll arrows
colorswatch: Remove unneeded save/restore

for both style context and cairo context.
configure: Require glib 2.43
gtkplacessidebar: Fix commit f6870e5b79fd9ab

Commit f6870e5b79fd9ab introduced a some memory leaks and could be
improved in some areas.

Fix the memory leaks and apply the improvements.

https://bugzilla.gnome.org/show_bug.cgi?id=737983