Close the sendCh once the connection is closed
Close the sendCh once the connection is closed

This avoids leaking the writeFrames goroutine

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