artifacts: Pass sysroot instead of buildroot.

BuildEbuildLogs... conflates buildroot with sysroot.
Adjust accordingly.

TEST=./run_tests
BUG=chromium:949566

Change-Id: I8cc2891d34cbb4abef0ed231332055a9fd096621
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/1558771
Tested-by: Evan Hernandez <evanhernandez@chromium.org>
Reviewed-by: Sean Abraham <seanabraham@chromium.org>
diff --git a/api/controller/artifacts_unittest.py b/api/controller/artifacts_unittest.py
index 6276b25..83773da 100644
--- a/api/controller/artifacts_unittest.py
+++ b/api/controller/artifacts_unittest.py
@@ -114,8 +114,9 @@
     self.assertEqual(
         [artifact.path for artifact in self.output_proto.artifacts],
         ['/tmp/artifacts/ebuild-logs.tar.gz'])
-    self.assertEqual(build_ebuild_logs_tarball.call_args_list,
-                     [mock.call('/cros', 'target', '/tmp/artifacts')])
+    self.assertEqual(
+        build_ebuild_logs_tarball.call_args_list,
+        [mock.call('/cros/chroot/build', 'target', '/tmp/artifacts')])
 
 
 class BundleTestUpdatePayloadsTest(cros_test_lib.MockTempDirTestCase):