[gtk/gtk-4-6: 1/2] frameclock: Run paint idle from flush idle

[Matthias Clasen <matthiasc src gnome org>]

commit 41396e1344156b5616ff93e8c627855ef4110415
Author: Benjamin Otte <otte redhat com>
Date:   Sun Jul 10 21:15:22 2022 +0200

    frameclock: Run paint idle from flush idle
    
    Don't return to the main loop, instead force a run of the paint idle.
    The paint idle will know to skip all the phases that aren't requested.
    
    This is critically important becuase gdksurface.c assumes the
    FLUSH_EVENTS and RESUME_EVENTS phases are matched, and we cannot
    guarantee that if we return to the main loop and let various reentrant
    code change the frame clock state.
    
    This would lead to bugs with events being paused and never unpaused
    again or even crashes.
    
    Fixes #4941

 gdk/gdkframeclockidle.c | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/gdk/gdkframeclockidle.c b/gdk/gdkframeclockidle.c
index 10c4e5cd2a..9c0c7263dd 100644
--- a/gdk/gdkframeclockidle.c
+++ b/gdk/gdkframeclockidle.c
@@ -373,6 +373,9 @@ gdk_frame_clock_flush_idle (void *data)
   else
     priv->phase = GDK_FRAME_CLOCK_PHASE_NONE;
 
+  g_clear_handle_id (&priv->paint_idle_id, g_source_remove);
+  gdk_frame_clock_paint_idle (data);
+
   return FALSE;
 }