heap: Cleanup clang plugin and BUILD.gn

Change-Id: Id29580a25849634d8a5a9dd173b097f57c1c90bf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2815298
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Yoav Weiss <yoavweiss@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#870888}
GitOrigin-RevId: fc6ecc30c38b9689a2e100b7a452ad14d7a04f9b
1 file changed