Revert "Roll third_party/flatbuffers."

This reverts commit cc1e52737abe0e4ce65e36bead7cbb32dd1e2b08.

Reason for revert: compile break the chromium tree

Original change's description:
> Roll third_party/flatbuffers.
>
> This rolls the commit range:
>   e3017029647a88eb6f509ee9744012fffeb0d371
>   a078130c878b0f997af24d532c6ade903ea7f65b
>
> Fixed: 1401327
> Change-Id: I4930f3e8eddac509dfe7a9443d5419b3304dd39b
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4111210
> Reviewed-by: Dominic Battré <battre@chromium.org>
> Reviewed-by: Balazs Engedy <engedy@chromium.org>
> Auto-Submit: Dominic Battré <battre@chromium.org>
> Commit-Queue: Dominic Battré <battre@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#1086040}

Change-Id: I23beae1665733a1a745d70133a4512ed9530b856
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4119371
Auto-Submit: Peter Williamson <petewil@chromium.org>
Commit-Queue: Dominic Battré <battre@chromium.org>
Reviewed-by: Dominic Battré <battre@chromium.org>
Owners-Override: Peter Williamson <petewil@chromium.org>
Quick-Run: Dominic Battré <battre@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1086051}