add video channel

Signed-off-by: fufesou <shuanglongchen@yeah.net>

src/server/input_service.rs

@@ -79,6 +79,8 @@ impl Subscriber for MouseCursorSub {
             self.inner.send(msg);
         }
     }
+
+    fn send_video_frame(&mut self, _: std::time::Instant, _: Arc<Message>) {}
 }
 
 pub const NAME_CURSOR: &'static str = "mouse_cursor";