Performance and stability improvements on all platforms.

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

Change-Id: I13f734bcd749b97a2a5cc4070675b55fe9638b8b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1582005
Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/7.6.18@{#1}
Cr-Branched-From: 784055ade07807e276f9d422373a9311f21048c3-refs/heads/master@{#60977}