[mutter] cursor-renderer/native: Warn when we start falling back on OpenGL

[Jonas Ådahl <jadahl src gnome org>]

commit 23924327807c5b433266f72097734f5dc5e1dda0
Author: Jonas Ådahl <jadahl gmail com>
Date:   Wed Mar 29 11:13:13 2017 +0800

    cursor-renderer/native: Warn when we start falling back on OpenGL
    
    When the driver unexpectedly fails setting the cursor sprite, log a
    warning that we from now on will use OpenGL.

 src/backends/native/meta-cursor-renderer-native.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/src/backends/native/meta-cursor-renderer-native.c 
b/src/backends/native/meta-cursor-renderer-native.c
index 4f7fcec..7028997 100644
--- a/src/backends/native/meta-cursor-renderer-native.c
+++ b/src/backends/native/meta-cursor-renderer-native.c
@@ -190,6 +190,9 @@ set_crtc_cursor (MetaCursorRendererNative *native,
                              priv->cursor_width, priv->cursor_height,
                              hot_x, hot_y) < 0)
         {
+          g_warning ("drmModeSetCursor2 failed with (%s), "
+                     "drawing cursor with OpenGL from now on",
+                     strerror (errno));
           priv->has_hw_cursor = FALSE;
           priv->hw_cursor_broken = TRUE;
         }