Revert "Remove sorting code from legacy hierarchy."

This reverts commit 36566a246acc7ccb767c23d267bc09ab82198985.

Reason for revert: The field type is not completely unused in Chrome. See the full context on  https://b.corp.google.com/issues/357838446#comment3

Original change's description:
> Remove sorting code from legacy hierarchy.
>
> The CL brings parity between Chrome's legacy hierarchy and the global
> model described on the public repo, which does not support sorting
> code.
>
> Note that the CL does not fully deprecate the ADDRESS_HOME_SORTING_CODE
> field type, it only removes it from the legacy hierarchy. Also, none
> of the country specific models support sorting code.
>
> Bug: 357838446
> Change-Id: I409b6ba3208da0bd40c09b5f23ecbe33432ff210
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5646085
> Reviewed-by: Dominic Battré <battre@chromium.org>
> Commit-Queue: Norge Vizcay <vizcay@google.com>
> Cr-Commit-Position: refs/heads/main@{#1338000}

Bug: 357838446
Change-Id: Id049c048ac9c758c178b3020e465b16bd2be9809
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5766226
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Dominic Battré <battre@chromium.org>
Reviewed-by: Dominic Battré <battre@chromium.org>
Auto-Submit: Norge Vizcay <vizcay@google.com>
Cr-Commit-Position: refs/heads/main@{#1338959}