What steps will reproduce the problem?
1. Create a lovely Chromium CL.
2. Rebase it.
3. Try to upload the rebase with git cl upload -t Rebase.

What is the expected output?

Expect that the CL successfully uploads, or errors out.

What do you see instead?

I repeatedly see the patch actually upload successfully, but the local command errors-out:

remote: Processing changes: updated: 1, done
remote: (W) 149e7dd: commit subject >50 characters; use shorter first paragraph
remote: (W) No changes between prior commit 527a02b and new commit 149e7dd
remote:
remote: Updated Changes:
remote:   https://chromium-review.googlesource.com/#/c/chromium/src/+/538439 Replace four Callbacks with a single Callback with Optional parameters.
remote:
To https://chromium.googlesource.com/chromium/src.git
 * [new branch]                149e7dd6a6f57ebd18ef9907e198124cd6baa496 -> refs/for/refs/heads/master%notify=NONE,m=Rebase

Error after CL description prompt -- saving description to C:\Users\wez/.git_cl_description_backup

Created|Updated 0 issues on Gerrit, but only 1 expected.
Change-Id: Iaed8af987b9992ae56689b704f18245a0f732571