Performance and stability improvements on all platforms.

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

Change-Id: Ic322fca2fa1dda0234c3a642cf42f98c9cb3443a
Reviewed-on: https://chromium-review.googlesource.com/c/1327191
Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/7.2.282@{#1}
Cr-Branched-From: dbbc38866afd72322aeafb4c4ef82fdbb771028d-refs/heads/master@{#57367}