code: public DbxDelta<DbxEntry> getDeltaWithPathPrefix(/*@Nullable*/String cursor, String pathPrefix,
                                                       boolean includeMediaInfo)
          throws DbxException
      {
          DbxPathV1.checkArg("path", pathPrefix);
          return _getDelta(cursor, pathPrefix, includeMediaInfo);
      }
docs: Same as {@link #getDelta}, except results are limited to files and folders whose
  paths are equal to or under the specified {@code pathPrefix}.
  
  <p>
  The {@code pathPrefix} is fixed for a given cursor.  Whatever {@code pathPrefix}
  you use on the first call to {@code getDelta()} must also be passed in on
  subsequent calls that use the returned cursor.
  </p>
  
  @param pathPrefix
  A path on Dropbox to limit results to.