rwm: remove stray reference to window cropping

This will likely be added in minor version 2 of the protocol after this
branch is finally merged to master.

 protocol/river-window-management-v1.xml | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/protocol/river-window-management-v1.xml b/protocol/river-window-management-v1.xml
index ac380ed..736a995 100644
--- a/protocol/river-window-management-v1.xml
+++ b/protocol/river-window-management-v1.xml
@@ -48,8 +48,7 @@
       Rendering state only affects the rendered output of the compositor and
       does not influence communication between the server and individual window
       clients. Rendering state includes the position and rendering order of
-      windows, shell surfaces, decoration surfaces, borders, window cropping,
-      and more.
+      windows, shell surfaces, decoration surfaces, borders, and more.
 
       Window management state may only be modified by the window manager as part
       of a manage sequence. A manage sequence is started with the manage_start