Merging Sandor's changes with backup (non-trivial merge)

MyTracks/src/com/google/android/apps/mytracks/stats/TripStatisticsBuilder.java

@@ -347,6 +347,8 @@ public class TripStatisticsBuilder {
    * Returns the amount of time the user has been idle or 0 if they are moving.
    */
   public long getIdleTime() {
+    if (lastLocation == null || lastMovingLocation == null)
+      return 0;
     return lastLocation.getTime() - lastMovingLocation.getTime();
   }