Performance and stability improvements on all platforms.

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

Change-Id: I32e5867f47190c8af85aa97f3bfc6905dfe5a779
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1591853
Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/7.6.80@{#1}
Cr-Branched-From: 9d53a080a88517bf800355b3d2f14601d136bd6d-refs/heads/master@{#61141}