Add the missing XML to byte array conversion method. While there, 1. Fix writeByteArrayXml method to store the hex chars of the value. 2. Cleanup couple of error strings in |readThisIntArrayXml| method. BUG: 29039296 Change-Id: I6386f7df7c5c8b7bc3bc5a268196da617209cea9 TEST: Compiles & manual testing.