Implement function to send m.location event

Allows to share the location with a room.

lib/src/room.dart

@@ -539,6 +539,17 @@ class Room {
     }, type: EventTypes.Reaction, txid: txid);
   }
 
+  /// Sends the location with description [body] and geo URI [geoUri] into a room.
+  /// Returns the event ID generated by the server for this message.
+  Future<String> sendLocation(String body, String geoUri, {String txid}) {
+    final event = <String, dynamic>{
+      'msgtype': 'm.location',
+      'body': body,
+      'geo_uri': geoUri,
+    };
+    return sendEvent(event, txid: txid);
+  }
+
   /// Sends a [file] to this room after uploading it. Returns the mxc uri of
   /// the uploaded file. If [waitUntilSent] is true, the future will wait until
   /// the message event has received the server. Otherwise the future will only

test/room_test.dart

@@ -434,6 +434,25 @@ void main() {
       });
     });
 
+    test('send location', () async {
+      FakeMatrixApi.calledEndpoints.clear();
+
+      final body = 'Middle of the ocean';
+      final geoUri = 'geo:0.0,0.0';
+      final dynamic resp =
+          await room.sendLocation(body, geoUri, txid: 'testtxid');
+      expect(resp.startsWith('\$event'), true);
+
+      final entry = FakeMatrixApi.calledEndpoints.entries
+          .firstWhere((p) => p.key.contains('/send/m.room.message/'));
+      final content = json.decode(entry.value.first);
+      expect(content, {
+        'msgtype': 'm.location',
+        'body': body,
+        'geo_uri': geoUri,
+      });
+    });
+
     // Not working because there is no real file to test it...
     /*test('sendImageEvent', () async {
       final File testFile = File.fromUri(Uri.parse("fake/path/file.jpeg"));