Performance and stability improvements on all platforms.

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

Change-Id: Ie51b01b6523f42f3a4cdcce6e63e31f0a09b2734
Reviewed-on: https://chromium-review.googlesource.com/c/1499593
Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/7.4.275@{#1}
Cr-Branched-From: 4633c78207743adf853768bbf0a8f571c8e98272-refs/heads/master@{#60005}