RFR: Section on backporting [v7]

[Kevin Rushforth]

On Thu, 2 Dec 2021 19:34:09 GMT, Jesper Wilhelmsson <jwilhelm at openjdk.org> wrote:

>> Guidance on backporting.
>> Also moved "Backing out a change" to the testing section where I believe it fits better. This section is unchanged.
>
> Jesper Wilhelmsson has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Fixes after review

I prefer option 1, but Jesper is right about the con of doing that.

Option 2 seems messy, although it might work.

Option 3 won't work since Skara forbids using a backport ID in a pull request (and I would not be in favor of changing that).

Option 4 seems too heavy-weight and error prone.

> I would propose to remove the backport link and then just do a new backport. This is the most simple approach for the developers working on the backports. Would this work with skara? Would the repeated bugId break any tooling?

Let's call this option 5 then. This won't break any tooling, and from a JBS point of view, won't be confusing. While I still don't much like the idea of having two commits in a repo with the same commit message but with different contents, this seems the most expedient approach. And as noted this should be very rare.

-------------

PR: https://git.openjdk.java.net/guide/pull/66