Performance and stability improvements on all platforms.

TBR=v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com

Change-Id: Icb0770ce8dd1e9addcec85a24453a06d04c094ec
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1645255
Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/7.7.21@{#1}
Cr-Branched-From: 2911a16fa6457f58b6ef48c22acbccede76a6063-refs/heads/master@{#61995}