Performance and stability improvements on all platforms.

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

Change-Id: Ic971fe300aed7f8e476debbd23869b7426db51ff
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1545990
Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/7.5.143@{#1}
Cr-Branched-From: 45535ba178fae9eb833d017f37516c94e178a3af-refs/heads/master@{#60520}