SensorManager handles SensorDataSet.

Part of #1424.

src/main/java/de/dennisguse/opentracks/services/handlers/TrackPointCreator.java

@@ -142,6 +142,11 @@ public class TrackPointCreator implements SensorManager.SensorDataSetChangeObser
         return sensorManager;
     }
 
+    @VisibleForTesting
+    public void setSensorManager(SensorManager sensorManager) {
+        this.sensorManager = sensorManager;
+    }
+
     @VisibleForTesting
     public void setClock(@NonNull String time) {
         this.clock = Clock.fixed(Instant.parse(time), ZoneId.of("CET"));