Revert "Fix tracking for generated IDs for most XML nodes"

This reverts commit ecbef02ae422921b6c69bb9aa53b88ccd50960f6.

Reason for revert: patch clobbers fields and causes wild derefs

Bug: 417859451
Original change's description:
> Fix tracking for generated IDs for most XML nodes
>
> - Delete the 16-bit constant for source ID masks, since libxml only
>   provides 32-bit fields now; 11 bits for the source ID is almost
>   certainly too few for even medium-sized documents.
> - Track generated IDs for XML nodes, et cetera so that subsequent
>   calls to generate-id() return the same value. This is the core of the
>   fix.
> - Simplify clearing the source ID information after the transform is
>   complete: it only requires zeroing out the extra field now, since
>   libxslt no longer tries to reuse random libxml fields in clever ways
>   for this particular purpose
>
> Bug: 417859451
> Change-Id: I54985a7a1b8aacc40c045e6008ea552f768e6d69
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6551500
> Reviewed-by: Kent Tamura <tkent@chromium.org>
> Commit-Queue: Daniel Cheng <dcheng@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#1461155}

Bug: 417859451
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Change-Id: I2e6a8371dadf609479ffb96e0e7e1660e3826023
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6553860
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Auto-Submit: Daniel Cheng <dcheng@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1461204}
NOKEYCHECK=True
GitOrigin-RevId: c402ca594da4e6f5de09a457f671760a3f94f8c2
3 files changed