spanification: Add `#pragma allow_unsafe_buffers` to core/svg/

https://chromium.googlesource.com/chromium/src/+/main/docs/unsafe_buffers.md#suppressions

This is a preparation to fix each files.
This CL has no behavior changes.

Bug: 351564777
Change-Id: I67c6135e5bb036cf58e8a56a4439c927f0a7c96a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5681758
Reviewed-by: danakj <danakj@chromium.org>
Commit-Queue: Kent Tamura <tkent@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1324625}
NOKEYCHECK=True
GitOrigin-RevId: 1215ca870e9e168e2f522c8a972f086d3571438f
1 file changed