netty: Include more stace trace information for ClosedChannelExceptions
netty: Include more stace trace information for ClosedChannelExceptions

There's been another sighting, but it's very hard to narrow down what is
triggering it.

ejona86/grpc-java,dapengzhang0/grpc-java,rmichela/grpc-java,zhangkun83/grpc-java,stanley-cheung/grpc-java,grpc/grpc-java,zhangkun83/grpc-java,dapengzhang0/grpc-java,ejona86/grpc-java,carl-mastrangelo/grpc-java,grpc/grpc-java,stanley-cheung/grpc-java,carl-mastrangelo/grpc-java,zhangkun83/grpc-java,carl-mastrangelo/grpc-java,elandau/grpc-java,grpc/grpc-java,dapengzhang0/grpc-java,stanley-cheung/grpc-java,stanley-cheung/grpc-java,ejona86/grpc-java,elandau/grpc-java,ejona86/grpc-java,carl-mastrangelo/grpc-java,rmichela/grpc-java,rmichela/grpc-java,grpc/grpc-java,elandau/grpc-java,dapengzhang0/grpc-java,rmichela/grpc-java,elandau/grpc-java,zhangkun83/grpc-java