bug 1442793 - generated sources artifact_prefix. r=bhearsum

MozReview-Commit-ID: 9vUBy1yMX8r

--HG--
extra : rebase_source : d9e13f10576960e7773c2cf1847b5b35859808d1

taskcluster/taskgraph/transforms/upload_generated_sources.py

@@ -34,6 +34,8 @@ def add_task_info(config, jobs):
         job['treeherder']['platform'] = plat
         job['treeherder']['tier'] = dep_th['tier']
         # Add an environment variable pointing at the artifact from the build.
+        # XXX This will break with any non-public artifact_prefix, but I believe
+        # these tasks are going away with buildbot.
         artifact_url = get_artifact_url('<build>',
                                         'public/build/target.generated-files.tar.gz')
         job['worker'].setdefault('env', {})['ARTIFACT_URL'] = {