Relui replaced release since Go 1.18 or so. We kept it around a bit
longer while there were remaining Go+BoringCrypto releases that still
used the release command. Those are no more, so to avoid confusion,
remove cmd/release code given it's no longer maintained or supported.

Updates golang/go#40279.
Updates golang/go#58659.
Fixes golang/go#45893.

Change-Id: Id0d641bee49c9584c52e5616322f0656b89cd851
Reviewed-on: https://go-review.googlesource.com/c/build/+/470755
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>

In 1.21, make.bash has a new argument, -distpack, which builds the
release archives reproducibly from any host architecture. See the
related bug for more details. This converts relui to use -distpack to
build everything.

Mostly that's as simple as adding an alternate build mode for the source
and binary archives. There are/were some wrinkles to work out:
- We need to generate the timestamp at the top level of the workflow so
  that the source consistency check reuses that same timestamp.
- Since we now get a zip out of the Windows build, we comically have to
  convert that back to a tarball to push it to a buildlet. Or at least I
  thought that was better than running unzip.
- I haven't figured out what to do about the module files yet. I think
  I'd prefer to recreate them in relui -- this code is really not happy
  about getting multiple files back from a build step.
- I didn't make a clear distinction between host and target builders in
  the BuildletStep. Maybe I should. But the distpack codepaths are so
  much smaller that it was easy to verify they didn't use the wrong
  config anywhere.

For golang/go#58659.

Change-Id: I4c4cf5b5450046a62d062d7c0bbfe94157ee9446
Reviewed-on: https://go-review.googlesource.com/c/build/+/478158
Run-TryBot: Heschi Kreinick <heschi@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Heschi Kreinick <heschi@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Carlos Amedee <carlos@golang.org>

Building on relui's new support for distpack builds, publish the
toolchain module files it generates. This turns out to be quite a
bit more complicated than I had hoped.

First, save the entire distpack archive, not just the binary
distribution. Extract the binary distribution for use in the normal
workflow. Then extract the modules files (really just the .zip, the
.mod and .info are tiny) to a separate artifact. Publish those to the
CDN alongside the normal release artifacts.

For non-distpack builds, copy the dl2mod code in from CL 475920 and
generate the module files as a postprocessing step on the binary
distribution.

The really annoying part is macOS, where we need to distribute the
signed binaries in the module, not the ones we built. For that, take the
module zip generated by distpack and replace the binaries with the ones
from the signed binary distribution. This is a fairly picky process, but
hopefully means we don't risk drifting out of sync with the canonical
distpacks.

Finally, the testing changes: the fake make.bash needs to emulate
distpack too, which wasn't too bad. And then the new requirement to
process the results of the macOS signing process means that the testing
fakes can't just produce cute text files -- they have to contain the
real distribution. Change the fake macOS packaging tools to deal in
prefixed tarballs.

For golang/go#58659.

Change-Id: I9cca8af2cb562fb39ef805a044109877b4ab7fb8
Reviewed-on: https://go-review.googlesource.com/c/build/+/482996
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

The intermediate PKG file is no longer a single line of plain text, it
has binary data (a release tarball) appended as of CL 482996. There is
a good chance said binary data will have a byte sequence that can't be
parsed as UTF-8 or some other character encoding without an error. sed
in turn fails with "sed: RE error: illegal byte sequence" on macOS.

Avoid this problem by using sed on the text and not the binary part of
the file.

For golang/go#58659.

Change-Id: If6acfed4c1f41c7ce3366679808614fecb98ec11
Reviewed-on: https://go-review.googlesource.com/c/build/+/487795
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>

Creating the module zips is surprisingly CPU-intensive, and we end up
doing it many times in parallel, resulting in it taking more than 10
minutes to finish and triggering the watchdog timer.

Disable the watchdog for this task, and give relui more CPU so that it's
less of a problem in the first place. (Collateral damage to other tasks
is still a concern.)

For golang/go#58659.

Change-Id: I65b5c47f9fdc011885c0d5f886f4050551d55f61
Reviewed-on: https://go-review.googlesource.com/c/build/+/489275
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Heschi Kreinick <heschi@google.com>

At some point the modules will be a key part of the release, just like
the website entries are now. Make sure that they're available on
proxy.golang.org before the release is announced.

For golang/go#58659.

Change-Id: I744c067f6efa06f3ca4cdbaf40a351f583331c16
Reviewed-on: https://go-review.googlesource.com/c/build/+/489415
Run-TryBot: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Heschi Kreinick <heschi@google.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

Try to shake out any reproducibility bugs by building each distpack
on two different host types.

For golang/go#58659

Change-Id: Ibe858909bf8469b71ba5c25c1588286f459101e8
Reviewed-on: https://go-review.googlesource.com/c/build/+/502537
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Auto-Submit: Heschi Kreinick <heschi@google.com>
Run-TryBot: Heschi Kreinick <heschi@google.com>