bindings: Update performance memory counters and expose legacy values

Legacy values are exposed via Origin Trial "Legacy Performance Memory
Counters", see details at
https://developers.chrome.com/origintrials/#/view_trial/2540030189836959745

Bug: 914304
Change-Id: If4bad6c4341ca7a05cf4f7c64c2850381f71b09a
Reviewed-on: https://chromium-review.googlesource.com/c/1373752
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Hitoshi Yoshida <peria@chromium.org>
Reviewed-by: Yuki Shiino <yukishiino@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#621664}
6 files changed