[Opus] Update to v1.2.1

third_party/opus/src/doc/release.txt

Index: third_party/opus/src/doc/release.txt
diff --git a/third_party/opus/src/doc/release.txt b/third_party/opus/src/doc/release.txt
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+= Release checklist =
+
+== Source release ==
+
+- Check for uncommitted changes to master.
+- Update OPUS_LT_* API versioning in configure.ac.
+- Tag the release commit with 'git tag -s vN.M'.
+ - Include release notes in the tag annotation.
+- Verify 'make distcheck' produces a tarball with
+  the desired name.
+- Push tag to public repo.
+- Upload source package 'opus-${version}.tar.gz'
+ - Add to https://svn.xiph.org/releases/opus/
+ - Update checksum files
+ - svn commit
+ - Copy to archive.mozilla.org/pub/opus/
+ - Update checksum files there as well.
+- Add release notes to https://git.xiph.org/opus-website.git
+- Update links and checksums on the downloads page.
+- Add a copy of the documentation to <https://www.opus-codec.org/docs/>
+  and update the links.
+- Update /topic in #opus IRC channel.
+
+Releases are commited to https://svn.xiph.org/releases/opus/
+which propagates to downloads.xiph.org, and copied manually
+to https://archive.mozilla.org/pub/opus/
+
+Website updates are committed to https://git.xiph.org/opus-website.git
+which propagates to https://opus-codec.org/
+
+== Binary release ==
+
+We usually build opus-tools binaries for MacOS and Windows.
+
+Binary releases are copied manually to
+https://archive.mozilla.org/pub/opus/win32/
+
+For Mac, submit a pull request to homebrew.
+
+== Website updates ==
+
+For major releases, recreate the files on https://opus-codec.org/examples/
+with the next encoder.