Capture/Replay Tests: Script cleanups. Minor cleanup changes and removes some outdated parameters. Includes logging information about how much time the script spends running each child process. Bug: angleproject:6102 Bug: angleproject:6299 Change-Id: I0b4da535b858ced3cdc21c341c2c001ffe9c8192 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3149190 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Cody Northrop <cnorthrop@google.com> Reviewed-by: Tim Van Patten <timvp@google.com>