[parser] Remove RETURN_IF* part 8

Bug: v8:8363, v8:7926
Change-Id: I6b08006397a70c2a9c35807a39c6d7e1ebf185e0
Reviewed-on: https://chromium-review.googlesource.com/c/1299025
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57004}