Performance and stability improvements on all platforms.

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

Change-Id: I72786ff458724a16cdceb6dd60de2ce06c4d129d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1536557
Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/7.5.99@{#1}
Cr-Branched-From: 5df31db0556cc684c1e1d48e0498c8e3cb234a3b-refs/heads/master@{#60415}