Live location share - open latest location in map site (#8981)

* move getForwardableBeacon to beacon utils

* move event transform type up

* add helper to get shareable-as-locaion events

* use getShareableLocationEvent in MessageContextMenu

* test opening in maplink

* fix bad copy pasted tests

src/utils/beacon/getShareableLocation.ts

@@ -0,0 +1,37 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import {
+    MatrixClient,
+    MatrixEvent,
+    getBeaconInfoIdentifier,
+} from "matrix-js-sdk/src/matrix";
+
+/**
+ * Beacons should only have shareable locations (open in external mapping tool, forward)
+ * when they are live and have a location
+ * If not live, returns null
+ */
+export const getShareableLocationEventForBeacon = (event: MatrixEvent, cli: MatrixClient): MatrixEvent | null => {
+    const room = cli.getRoom(event.getRoomId());
+    const beacon = room.currentState.beacons?.get(getBeaconInfoIdentifier(event));
+    const latestLocationEvent = beacon?.latestLocationEvent;
+
+    if (beacon?.isLive && latestLocationEvent) {
+        return latestLocationEvent;
+    }
+    return null;
+};