Performance and stability improvements on all platforms.

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

Change-Id: Ia8ccdd1e87f4ca89aa1827f06c3a4dbb670727f1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1560217
Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/7.5.226@{#1}
Cr-Branched-From: 0b1e9ef244c0e9e92bb477938e6de4df5c3ac841-refs/heads/master@{#60723}