Each of those types have to split off a single actual instance type.
There can be many that split off the same instance type.

Bug: v8:7266
Change-Id: Ic78b707e26e67bdd2072cd8a716c89eaae024e48
Reviewed-on: https://chromium-review.googlesource.com/860651Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50530}