Location sharing - extract isSelfLocation util (#8279)

* extract isSelfLocation into utils

Signed-off-by: Kerry Archibald <kerrya@element.io>

* replace use of isSelfLocation

Signed-off-by: Kerry Archibald <kerrya@element.io>

src/utils/location/index.ts

@@ -15,6 +15,7 @@ limitations under the License.
 */
 
 export * from './findMapStyleUrl';
+export * from './isSelfLocation';
 export * from './locationEventGeoUri';
 export * from './LocationShareErrors';
 export * from './map';

src/utils/location/isSelfLocation.ts

@@ -0,0 +1,23 @@
+/*
+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 { ILocationContent, LocationAssetType, M_ASSET } from "matrix-js-sdk/src/@types/location";
+
+export const isSelfLocation = (locationContent: ILocationContent): boolean => {
+    const asset = M_ASSET.findIn(locationContent) as { type: string };
+    const assetType = asset?.type ?? LocationAssetType.Self;
+    return assetType == LocationAssetType.Self;
+};