Fix #180 - "I don't know what to do with a core file when logPrefix is null" shown due to str/unicode confusion
Fix #180 - "I don't know what to do with a core file when logPrefix is null" shown due to str/unicode confusion

nth10sd/funfuzz,nth10sd/funfuzz,MozillaSecurity/funfuzz,nth10sd/funfuzz,MozillaSecurity/funfuzz,MozillaSecurity/funfuzz