[mutter] MonitorManager: return the new backlight after changing

[Giovanni Campagna <gcampagna src gnome org>]

commit a3037a6dd1bb7fceeea380658651861b349e3420
Author: Giovanni Campagna <gcampagn redhat com>
Date:   Mon Aug 26 17:27:33 2013 +0200

    MonitorManager: return the new backlight after changing
    
    Modify the interface of ChangeBacklight to return the new value,
    to account for rounding to HW limits.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=706729

 src/core/monitor.c |    2 +-
 src/xrandr.xml     |    3 +++
 2 files changed, 4 insertions(+), 1 deletions(-)
---
diff --git a/src/core/monitor.c b/src/core/monitor.c
index e3e81ab..c6b4649 100644
--- a/src/core/monitor.c
+++ b/src/core/monitor.c
@@ -1228,7 +1228,7 @@ meta_monitor_manager_handle_change_backlight  (MetaDBusDisplayConfig *skeleton,
 
   META_MONITOR_MANAGER_GET_CLASS (manager)->change_backlight (manager, output, value);
 
-  meta_dbus_display_config_complete_change_backlight (skeleton, invocation);
+  meta_dbus_display_config_complete_change_backlight (skeleton, invocation, output->backlight);
   return TRUE;
 }
 
diff --git a/src/xrandr.xml b/src/xrandr.xml
index d8574ad..06449c3 100644
--- a/src/xrandr.xml
+++ b/src/xrandr.xml
@@ -205,11 +205,14 @@
 
        Changes the backlight of @output to @value, which is
        expressed as a percentage and rounded to the HW limits.
+
+        Returns the new value after rounding.
     -->
     <method name="ChangeBacklight">
       <arg name="serial" direction="in" type="u" />
       <arg name="output" direction="in" type="u" />
       <arg name="value" direction="in" type="i" />
+      <arg name="new_value" direction="out" type="i" />
     </method>
 
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