GitLab

Uses new V8::GetSharedMemoryStatistics API to report stats on shared
memory in V8 (i.e. not per isolate) such as read_only_space's size.

Bug: v8:7464
Change-Id: I139e084c51703dd5cf1239a59128de874aea62c4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1905547
Commit-Queue: Dan Elphick <delphick@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#714262}