Pass empty email & password to ReadOnlyRietveld in dry run of commit queue

commit_queue.py

Index: commit_queue.py
diff --git a/commit_queue.py b/commit_queue.py
index 8bb63acca00fb18d564e6f7449b9ec0e210aeb71..fce6c33ff404223d3ed50917317c4c35993a7ba3 100755
--- a/commit_queue.py
+++ b/commit_queue.py
@@ -224,12 +224,10 @@ def main():
         parser.error('--only-issue is not supported with dry run')
       else:
         print('Using read-only Rietveld')
-      # Make sure rietveld is not modified.
-      rietveld_obj = rietveld.ReadOnlyRietveld(
-          url,
-          options.user,
-          gaia_creds.get(options.user),
-          None)
+      # Make sure rietveld is not modified. Pass empty email and
+      # password to bypass authentication; this additionally
+      # guarantees rietveld will not allow any changes.
+      rietveld_obj = rietveld.ReadOnlyRietveld(url, email='', password='')
     else:
       AlertOnUncleanCheckout()
       print('WARNING: The Commit Queue is going to commit stuff')