[gtk+/wip/wayland-tablet: 1249/1271] device: Add GDK_AXIS_DISTANCE GdkAxisUse value

[Carlos Garnacho <carlosg src gnome org>]

commit 4c1c829410527bc18c2450d6aa273006abb0c642
Author: Carlos Garnacho <carlosg gnome org>
Date:   Tue Jan 27 21:34:21 2015 +0000

    device: Add GDK_AXIS_DISTANCE GdkAxisUse value
    
    This is something we can represent on a fairly wide range of devices, so
    add a value for this in the axis enum.

 gdk/gdkdevice.h |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/gdk/gdkdevice.h b/gdk/gdkdevice.h
index 4894772..e51b15b 100644
--- a/gdk/gdkdevice.h
+++ b/gdk/gdkdevice.h
@@ -89,6 +89,7 @@ typedef enum
  * @GDK_AXIS_XTILT: the axis is used for x tilt information.
  * @GDK_AXIS_YTILT: the axis is used for y tilt information.
  * @GDK_AXIS_WHEEL: the axis is used for wheel information.
+ * @GDK_AXIS_DISTANCE: the axis is used for pen/tablet distance information..
  * @GDK_AXIS_LAST: a constant equal to the numerically highest axis value.
  *
  * An enumeration describing the way in which a device
@@ -104,6 +105,7 @@ typedef enum
   GDK_AXIS_XTILT,
   GDK_AXIS_YTILT,
   GDK_AXIS_WHEEL,
+  GDK_AXIS_DISTANCE,
   GDK_AXIS_LAST
 } GdkAxisUse;