[mutter/wip/underscan: 2/2] monitor-manager-xrandr: don't set underscan property when not supported

[Cosimo Cecchi <cosimoc src gnome org>]

commit 49e0bd58df614c1b76020fff8ebe9697b0181ab1
Author: Cosimo Cecchi <cosimoc gnome org>
Date:   Wed Jul 1 17:59:36 2015 -0700

    monitor-manager-xrandr: don't set underscan property when not supported
    
    We should not be setting random output properties like this.
    Use the function we just introduced to only set the underscan flag when
    it's actually supported.

 src/backends/x11/meta-monitor-manager-xrandr.c |    7 ++++---
 1 files changed, 4 insertions(+), 3 deletions(-)
---
diff --git a/src/backends/x11/meta-monitor-manager-xrandr.c b/src/backends/x11/meta-monitor-manager-xrandr.c
index 86d24b5..dd10c38 100644
--- a/src/backends/x11/meta-monitor-manager-xrandr.c
+++ b/src/backends/x11/meta-monitor-manager-xrandr.c
@@ -1209,9 +1209,10 @@ meta_monitor_manager_xrandr_apply_configuration (MetaMonitorManager *manager,
                                       output_info->output,
                                       output_info->is_presentation);
 
-      output_set_underscanning_xrandr (manager_xrandr,
-                                       output_info->output,
-                                       output_info->is_underscanning);
+      if (output_get_supports_underscanning_xrandr (manager_xrandr, output_info->output))
+        output_set_underscanning_xrandr (manager_xrandr,
+                                         output_info->output,
+                                         output_info->is_underscanning);
 
       output->is_primary = output_info->is_primary;
       output->is_presentation = output_info->is_presentation;