Tracing: make emptyTracing an actual Tracing object
Tracing: make emptyTracing an actual Tracing object

Zirpon/tchannel,benfleis/tchannel,chenwenbin928/tchannel,benfleis/tchannel,savaki/tchannel,bunnyblue/tchannel,sasa233/tchannel,bunnyblue/tchannel,i/tchannel,hustxiaoc/tchannel,RyanTech/tchannel,i/tchannel,RyanTech/tchannel,hustxiaoc/tchannel,Zirpon/tchannel,bunnyblue/tchannel,sasa233/tchannel,savaki/tchannel,vanloswang/tchannel,Zirpon/tchannel,sasa233/tchannel,savaki/tchannel,chenwenbin928/tchannel,vanloswang/tchannel,hustxiaoc/tchannel,benfleis/tchannel,vanloswang/tchannel,chenwenbin928/tchannel,RyanTech/tchannel,i/tchannel