Plus a bit of CSA typification.

Bug: v8:7725
Change-Id: I43fea4a4c0739f9c24d84035816b046e742372ee
Reviewed-on: https://chromium-review.googlesource.com/1051653Reviewed-by: Marja Hölttä <marja@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53102}