[fix] fix non-existent function call in File transport.
[fix] fix non-existent function call in File transport.

megastef/winston,harriha/winston,rakesh-mohanta/winston,winstonjs/winston,apiaryio/winston,nikolas/winston,s-panferov/winston,z-10/winston,alphagov/winston,dbmikus/winston,get-trucked/winston,uber/winston,jjmleiro/winston,auth0/winston,tobli/winston,dustinblackman/winston,paulhroth/winston,modulexcite/winston,pantheon-systems/winston,thaliproject/winston,whismat/winston,beni55/winston,aquavitae/winston,DenisGorbachev/winston,alinex/winston,psquickitjayant/winston,unlucio/winston,wancharle/winston,SmartNode-es/winston,winstonjs/winston