[poppler] Object management helper class

[Jakub Kucharski]

On Mon, 2016-05-30 at 23:52 +0200, Jakub Kucharski wrote:
> If I get your reasoning right, you just want to cause compiler to
> point
> out the places where free() and operator= are used and then correct
> it
> by hand. I think it's a good idea, but perhaps it would be easier if
> we
> took care of the warnings we get now, so we would notice if any new
> turned up after the change (aside from genuine errors). Just a
> thought.

Started looking into the warning about
gtk_style_context_get_background_color() and found this:
https://bugs.freedesktop.org/show_bug.cgi?id=96282

		Jakub