Fix NPE in o.b.c.Utils runtime and os detection
Fix NPE in o.b.c.Utils runtime and os detection

If getProperty returns null calling toLowerCase results in NPE. Instead
we’ll use a default value and check for .equals(“”) in the following if.

peterdettman/bitcoinj,bitcoinj/bitcoinj,natzei/bitcoinj,schildbach/bitcoinj,schildbach/bitcoinj,bitcoinj/bitcoinj,peterdettman/bitcoinj,natzei/bitcoinj,yenliangl/bitcoinj,yenliangl/bitcoinj