Performance and stability improvements on all platforms.

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

Change-Id: I4bac6623ff1635edf53556c31ee928c9dbe1776c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1582002
Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/7.6.17@{#1}
Cr-Branched-From: 5f652b84c0f6049f8c9c4c8630e1f37b1a2b263c-refs/heads/master@{#60974}