Revert "When GuestMetrics are NULL, update_vm is partial"

Author: robhoes

ocaml/xapi/xapi_xenops.ml

@@ -1460,11 +1460,8 @@ let update_vm ~__context id =
               (fun (_, state) ->
                  let gm = Db.VM.get_guest_metrics ~__context ~self in
                  debug "xenopsd event: Updating VM %s PV drivers detected %b" id state.pv_drivers_detected;
-                 try
-                   Db.VM_guest_metrics.set_PV_drivers_detected ~__context ~self:gm ~value:state.pv_drivers_detected;
-                   Db.VM_guest_metrics.set_PV_drivers_up_to_date ~__context ~self:gm ~value:state.pv_drivers_detected
-                 with e ->
-                   error "Caught %s: while updating VM %s PV driver detection" (Printexc.to_string e) id
+                 Db.VM_guest_metrics.set_PV_drivers_detected ~__context ~self:gm ~value:state.pv_drivers_detected;
+                 Db.VM_guest_metrics.set_PV_drivers_up_to_date ~__context ~self:gm ~value:state.pv_drivers_detected
               ) info in
           Opt.iter
             (fun (_, state) ->