[gtk+] x11: Add call to XInitThreads()

[Benjamin Otte <otte src gnome org>]

commit d54117024c08b2de3f2ea08a3730040734a1bd43
Author: Benjamin Otte <otte redhat com>
Date:   Thu Jan 12 02:01:07 2017 +0100

    x11: Add call to XInitThreads()
    
    The Mesa Vulkan drivers need XInitThreads() being called, because their
    implementation has to use threads.
    
    And I don't want to make the call depend on if Vulkan is compiled in
    because that makes GTK's X11 behavior depend on compile-time flags, so
    it's always called.

 gdk/x11/gdkdisplay-x11.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/gdk/x11/gdkdisplay-x11.c b/gdk/x11/gdkdisplay-x11.c
index 547a9ae..ae706bb 100644
--- a/gdk/x11/gdkdisplay-x11.c
+++ b/gdk/x11/gdkdisplay-x11.c
@@ -1367,6 +1367,8 @@ _gdk_x11_display_open (const gchar *display_name)
   gint ignore;
   gint maj, min;
 
+  XInitThreads ();
+
   xdisplay = XOpenDisplay (display_name);
   if (!xdisplay)
     return NULL;