[master] golang format tools (#2858)
[master] golang format tools (#2858)

Produced via:
  `gofmt -s -w $(find -path './vendor' -prune -o -path './third_party' -prune -o -type f -name '*.go' -print)`
  `goimports -w $(find -name '*.go' | grep -v vendor | grep -v third_party)`
/assign grantr n3wscott
/cc grantr n3wscott
knative/eventing,knative/eventing