Merge "Log warning when can't read from HW RNG"

     * Mixes in the output from HW RNG (if present) into the Linux RNG.

     */

    private void addHwRandomEntropy() {

        if (!new File(hwRandomDevice).exists()) {

            // HW RNG not present/exposed -- ignore

            return;

        }

        try {

            RandomBlock.fromFile(hwRandomDevice).toFile(randomDevice, false);

            Slog.i(TAG, "Added HW RNG output to entropy pool");

        } catch (FileNotFoundException ignored) {

            // HW RNG not present/exposed -- ignore

        } catch (IOException e) {

            Slog.w(TAG, "Failed to add HW RNG output to entropy pool", e);

        }