private int unsignedBytesToInt(byte b0, byte b1) {
        return (unsignedByteToInt(b0) + (unsignedByteToInt(b1) << 8));
    }
Used for mocks and constants in rxandroidble, but instances created in mockrxandroidble, so the methods must be implemented
rxandroidble/src/test/java/android/bluetooth/BluetoothGattCharacteristic.java