Minimize serialization diff with mainline

[liach]

For preview of the serialization implementation cleanup.

See the mainline diff version:
https://gist.github.com/a3440f2b9da5111fe20315e59ed17380

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Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change must be properly reviewed (1 review required, with at least 1 Committer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/valhalla.git pull/2326/head:pull/2326
$ git checkout pull/2326

Update a local copy of the PR:
$ git checkout pull/2326
$ git pull https://git.openjdk.org/valhalla.git pull/2326/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 2326

View PR using the GUI difftool:
$ git pr show -t 2326

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/valhalla/pull/2326.diff

[bridgekeeper]

👋 Welcome back liach! A progress list of the required criteria for merging this PR into lworld will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[liach]

/template append

[openjdk]

@liach The pull request template has been appended to the pull request body