This reverts commit a7d6bf96.

Reason for revert: GN breakage preventing lkgr: https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Blink%20Linux/16971/overview

Original change's description:
> [test] Move tracing cctest to unittests
>
> Bug: v8:12781
> Change-Id: Idc50a20f17de3af25372833b28cb16ac9a0e6485
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3574552
> Auto-Submit: Leszek Swirski <leszeks@chromium.org>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#80065}

Bug: v8:12781
Change-Id: Icb295f7203cec4aef4bda491d08a39ce0c66fa0b
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3597242
Auto-Submit: Shu-yu Guo <syg@chromium.org>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#80068}