[cogl] kms-winsys: don't wait for a flip when page flipping fails

[Ray Strode <halfline src gnome org>]

commit b78052f60fa3bc149f8dd33f80d6056283563c4a
Author: Ray Strode <rstrode redhat com>
Date:   Wed Oct 21 15:47:01 2015 -0400

    kms-winsys: don't wait for a flip when page flipping fails
    
    If we get EACCES from drmPageFlip we're not going to get
    a flip event and shouldn't wait for one.
    
    This commit changes the EACCES path to silently ignore the
    failed flip request and just clean up the fb.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=756926

 cogl/winsys/cogl-winsys-egl-kms.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)
---
diff --git a/cogl/winsys/cogl-winsys-egl-kms.c b/cogl/winsys/cogl-winsys-egl-kms.c
index 2be1629..c192c26 100644
--- a/cogl/winsys/cogl-winsys-egl-kms.c
+++ b/cogl/winsys/cogl-winsys-egl-kms.c
@@ -580,7 +580,7 @@ flip_all_crtcs (CoglDisplay *display, CoglFlipKMS *flip, int fb_id)
   for (l = kms_display->crtcs; l; l = l->next)
     {
       CoglKmsCrtc *crtc = l->data;
-      int ret;
+      int ret = 0;
 
       if (crtc->count == 0 || crtc->ignore)
         continue;
@@ -595,7 +595,8 @@ flip_all_crtcs (CoglDisplay *display, CoglFlipKMS *flip, int fb_id)
           continue;
         }
 
-      flip->pending++;
+      if (ret == 0)
+        flip->pending++;
     }
 }