gistfile.diff

diff --git a/testing/mozharness/mozharness/mozilla/taskcluster_helper.py b/testing/mozharness/mozharness/mozilla/taskcluster_helper.py
--- a/testing/mozharness/mozharness/mozilla/taskcluster_helper.py
+++ b/testing/mozharness/mozharness/mozilla/taskcluster_helper.py
@@ -72,43 +72,62 @@ class Taskcluster(LogMixin):
             {
                 "workerGroup": self.buildbot,
                 "workerId": self.buildbot,
             })
 
     def get_task(self, task_id):
         return self.taskcluster_queue.task(task_id)
 
-    def create_artifact(self, task, filename):
+    @staticmethod
+    def get_mime_type(ext, default='application/octet-stream'):
         mime_types = {
             ".asc": "text/plain",
             ".checksums": "text/plain",
             ".json": "application/json",
             ".log": "text/plain",
             ".tar.bz2": "application/x-gtar",
             ".txt": "text/plain",
             ".xpi": "application/x-xpinstall",
             ".zip": "application/zip",
         }
-        mime_type = mime_types.get(os.path.splitext(filename)[1], 'application/octet-stream')
+        return mime_types.get(ext, default)
+
+    def create_artifact(self, task, filename):
+        mime_type = self.get_mime_type(os.path.splitext(filename)[1])
         content_length = os.path.getsize(filename)
-
-        self.info("Uploading to S3: filename=%s mimetype=%s length=%s" % (filename, mime_type, content_length))
+        self.info("Uploading to S3: filename=%s mimetype=%s length=%s" % (
+            filename, mime_type, content_length))
 
         expiration = datetime.utcnow() + timedelta(weeks=52)
         artifact = self.taskcluster_queue.createArtifact(
             task['status']['taskId'],
             task['status']['runs'][-1]['runId'],
             'public/build/%s' % os.path.basename(filename),
             {
                 "storageType": "s3",
                 "expires": expiration,
                 "contentType": mime_type,
             })
         self.put_file(filename, artifact['putUrl'], mime_type)
+        return self.get_taskcluster_url(filename)
+
+    def create_reference_artifact(self, task, filename, url):
+        mime_type = self.get_mime_type(os.path.splitext(filename)[1])
+        expiration = datetime.utcnow() + timedelta(weeks=52)
+        self.taskcluster_queue.createArtifact(
+            task['status']['taskId'],
+            task['status']['runs'][-1]['runId'],
+            'public/build/%s' % os.path.basename(filename),
+            {
+                "storageType": "reference",
+                "expires": expiration,
+                "contentType": mime_type,
+                "url": url,
+            })
 
     def report_completed(self, task):
         self.taskcluster_queue.reportCompleted(
             task['status']['taskId'],
             task['status']['runs'][-1]['runId'],
             {
                 "success": True,
             })
diff --git a/testing/mozharness/scripts/desktop_l10n.py b/testing/mozharness/scripts/desktop_l10n.py
--- a/testing/mozharness/scripts/desktop_l10n.py
+++ b/testing/mozharness/scripts/desktop_l10n.py
@@ -1006,19 +1006,20 @@ class DesktopSingleLocale(LocalesMixin, 
             task = tc.create_task(routes)
             tc.claim_task(task)
 
             for upload_file in files:
                 # Create an S3 artifact for each file that gets uploaded. We also
                 # check the uploaded file against the property conditions so that we
                 # can set the buildbot config with the correct URLs for package
                 # locations.
-                tc.create_artifact(task, upload_file)
+                artifact_url = tc.create_artifact(task, upload_file)
                 if bbb_task:
-                    # Also attach the artifact to BBB task
-                    tc.create_artifact(bbb_task, upload_file)
+                    # Also attach the artifact to BBB task as a reference
+                    tc.create_reference_artifact(bbb_task, upload_file,
+                                                 artifact_url)
 
             tc.report_completed(task)
 
 # main {{{
 if __name__ == '__main__':
     single_locale = DesktopSingleLocale()
     single_locale.run_and_exit()