Function has_property_on_prototype 

pub fn has_property_on_prototype(
    cx: &mut JSContext,
    proxy: HandleObject<'_>,
    id: HandleId<'_>,
    found: &mut bool,
) -> bool

Computes whether proxy has a property id on its prototype and stores the result in found.

Returns a boolean indicating whether the check succeeded. If false is returned then the value of found is unspecified.