Auto-update dependencies (#920)

Produced via:
  `dep ensure -update knative.dev/test-infra`
/assign n3wscott

Gopkg.lock

@@ -1296,14 +1296,14 @@
 
 [[projects]]
   branch = "master"
-  digest = "1:85fe0cadd6ab83f3d7f948c60b6d422dc9cd16664246249968dab5d828ae8dfd"
+  digest = "1:6e839a9b4183b0fbf0df609fe9a6d226c941fa9221052ba0075b25cb353588a5"
   name = "knative.dev/test-infra"
   packages = [
     "scripts",
     "tools/dep-collector",
   ]
   pruneopts = "UT"
-  revision = "2c4cd9df33c648a86d95bdd4119386cba04cde56"
+  revision = "9363d2f4cafd2ad3c1bfc925f447c91a1776be00"
 
 [[projects]]
   digest = "1:8730e0150dfb2b7e173890c8b9868e7a273082ef8e39f4940e3506a481cf895c"

vendor/knative.dev/test-infra/scripts/presubmit-tests.sh

@@ -156,8 +156,10 @@ function default_build_test_runner() {
   markdown_build_tests || failed=1
   # For documentation PRs, just check the md files
   (( IS_DOCUMENTATION_PR )) && return ${failed}
+  # Don't merge these two lines, or return code will always be 0.
+  local go_pkg_dirs
+  go_pkg_dirs="$(go list ./...)" || return 1
   # Skip build test if there is no go code
-  local go_pkg_dirs="$(go list ./...)"
   [[ -z "${go_pkg_dirs}" ]] && return ${failed}
   # Ensure all the code builds
   subheader "Checking that go code builds"