Fix NPE

    private final String mPrimaryDeviceType;

    /* Scan results handling */

    private List<ScanResult> mScanResults;

    private List<ScanResult> mScanResults = new ArrayList<ScanResult>();

    private static final Pattern scanResultPattern = Pattern.compile("\t+");

    private static final int SCAN_RESULT_CACHE_SIZE = 80;

    private final LruCache<String, ScanResult> mScanResultCache;