This CL adds CheckRange() which will be used in DCHECKs in BoundedPageAllocator
and renames "min_region_size" to "page_size" for better readability.

Bug: v8:8096
Change-Id: I62cf7a92e50d0a11d462a9fbc34ddc5eda5456e1
Reviewed-on: https://chromium-review.googlesource.com/1209284Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55692}