pkg/52570: audio/libcanberra does not build on Darwin

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>Number:         52570
>Category:       pkg
>Synopsis:       audio/libcanberra does not build on Darwin
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Sep 23 12:10:00 +0000 2017
>Originator:     Jonathan Schleifer
>Release:        HEAD
>Organization:
>Environment:
>Description:
audio/libcanberra does not build on Darwin because it wants to use gdkx:
canberra-gtk.c:29:10: fatal error: 'gdk/gdkx.h' file not found
#include <gdk/gdkx.h>
         ^~~~~~~~~~~~

But gtk2 is built without x11 on Darwin.
>How-To-Repeat:

>Fix:
MacPorts has a patch:

https://trac.macports.org/browser/trunk/dports/audio/libcanberra/files/patch-gtkquartz.diff?rev=77611