[libdazzle] graph: use monotonic clock for time

[Christian Hergert <chergert src gnome org>]

commit 8a89a335eb0504e6ee1362d6ef05c3825e50025c
Author: Christian Hergert <chergert redhat com>
Date:   Tue Feb 27 18:34:38 2018 -0800

    graph: use monotonic clock for time
    
    We can't rely on frame time, since that seems to have shifted
    in recent gtk+ commits to avoid jitter.
    
    I'd like to use the frame time, but that probably puts undue
    requirements on the graph model.

 src/graphing/dzl-graph-view.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/graphing/dzl-graph-view.c b/src/graphing/dzl-graph-view.c
index 0b84588..43f92d9 100644
--- a/src/graphing/dzl-graph-view.c
+++ b/src/graphing/dzl-graph-view.c
@@ -131,7 +131,7 @@ dzl_graph_view_tick_cb (GtkWidget     *widget,
 
   gtk_widget_get_allocation (widget, &alloc);
 
-  frame_time = gdk_frame_clock_get_frame_time (frame_clock);
+  frame_time = g_get_monotonic_time ();
   end_time = dzl_graph_view_model_get_end_time (priv->model);
 
   x_offset = -((frame_time - end_time) / (gdouble)timespan);