Kusama origins as xcm multi_location (#6273)

* Kusamsa origins as xcm multilocation

* Fellows origin index

* origins to xcm plurality body

* cleanup

* fix cargo spellcheck

* Apply suggestions from code review

Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com>

* include Fellows into scope

* include Fellows into scope

Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com>
Co-authored-by: Gavin Wood <gavin@parity.io>

polkadot/xcm/xcm-builder/src/origin_conversion.rs

@@ -321,3 +321,20 @@ where
 		})
 	}
 }
+
+/// `Convert` implementation to convert from an origin which passes the check of an `EnsureOrigin`
+/// into a voice of a given pluralistic `Body`.
+pub struct OriginToPluralityVoice<RuntimeOrigin, EnsureBodyOrigin, Body>(
+	PhantomData<(RuntimeOrigin, EnsureBodyOrigin, Body)>,
+);
+impl<RuntimeOrigin: Clone, EnsureBodyOrigin: EnsureOrigin<RuntimeOrigin>, Body: Get<BodyId>>
+	Convert<RuntimeOrigin, MultiLocation>
+	for OriginToPluralityVoice<RuntimeOrigin, EnsureBodyOrigin, Body>
+{
+	fn convert(o: RuntimeOrigin) -> Result<MultiLocation, RuntimeOrigin> {
+		match EnsureBodyOrigin::try_origin(o) {
+			Ok(_) => Ok(Junction::Plurality { id: Body::get(), part: BodyPart::Voice }.into()),
+			Err(o) => Err(o),
+		}
+	}
+}