This reverts commit eff810e93d.
Reason for revert: breaks workflows for users
Original change's description:
> Error out of rebase-update if there are uncommitted changes
>
> Currently, running rebase-update may lead to missing untracked files.
> This change prints an error instead freezing and thawing local changes.
>
> Bug: 1251047
> Change-Id: Ia5f718ed957dae936d2ead2778760ae0c8d9f9ea
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3171828
> Commit-Queue: Gavin Mak <gavinmak@google.com>
> Reviewed-by: Josip Sokcevic <sokcevic@google.com>
Bug: 1251047
Change-Id: I5b61dc1c7af13ccca6ea80baecff0522291083c9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3191674
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Gavin Mak <gavinmak@google.com>