[PATCH wayland] protocol: Add a surface_has_existing_role error

[Jasper St. Pierre]

This will be used by implementations to send out errors if clients try
to set roles on surfaces that already have roles.
---
 protocol/wayland.xml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/protocol/wayland.xml b/protocol/wayland.xml
index bb457bc..f6eb54d 100644
--- a/protocol/wayland.xml
+++ b/protocol/wayland.xml
@@ -983,6 +983,7 @@
       </description>
       <entry name="invalid_scale" value="0" summary="buffer scale value is invalid"/>
       <entry name="invalid_transform" value="1" summary="buffer transform value is invalid"/>
+      <entry name="surface_has_existing_role" value="2" summary="the surface passed already has a role"/>
     </enum>
 
     <request name="destroy" type="destructor">
-- 
2.1.0