Hide the wrapping shader source

Change-Id: I4841e97be343a9f7141c69e5b85bf17d0a39db55

qml/conveyor/Conveyor.qml

@@ -153,6 +153,8 @@ Item {
         sourceItem: viewport
         width: viewport.width
         height: viewport.height
+        hideSource: true
+        live: true
     }
 
     ShaderEffect {