Code review: 36230043: Minor bug fix in the event lib.
Code review: 36230043: Minor bug fix in the event lib.

Onager/plaso,rgayon/plaso,log2timeline/plaso,kiddinn/plaso,joachimmetz/plaso,Onager/plaso,log2timeline/plaso,joachimmetz/plaso,rgayon/plaso,kiddinn/plaso,kiddinn/plaso,rgayon/plaso