Synchronizing repo with outside snapshot.xml

[dick.r...@gmail.com]

Suppose I start with:

repo init -u https://cos.googlesource.com/cos/manifest.git

How to now have repo sync according to an outside manifest found at

https://cos.googlesource.com/cos/manifest-snapshots/+/refs/tags/13310.1209.3/snapshot.xml

In other words, I want the equivalent of a `git checkout tag`.

[dick.r...@gmail.com]

vap...@chromium.org has responded to me on chromium-os-discussion with

> repo init -c -u https://cos.googlesource.com/cos/manifest-snapshots -b
> refs/tags/13310.1209.3 -m snapshot.xml

This looks very good! Sorry for the cross-post noise.