Revert of Process Statistics header, add max RSS to render_pdfs (https://codereview.chromium.org/448993003/)

Reason for revert:
Reverting due to breaking iOS bots.

Original issue's description:
> Process Statistics header, add max RSS to render_pdfs
>
> Committed: https://skia.googlesource.com/skia/+/6274baae7fe82ce6481da367687aa6168356e1e1

R=mtklein@google.com, halcanary@google.com
TBR=halcanary@google.com, mtklein@google.com
NOTREECHECKS=true
NOTRY=true

Author: bungeman@google.com

Review URL: https://codereview.chromium.org/448243003
6 files changed