📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/13ff04a1140000

Issue 915660 has been merged into this issue.

📍 Found a significant difference after 1 commit.
https://pinpoint-dot-chromeperf.appspot.com/job/13ff04a1140000

Roll src/clank 3a6fac8b3e6d..01993c05e782 (1 commits) by chromium-internal-autoroll@skia-corp.google.com.iam.gserviceaccount.com
https://chrome-internal.googlesource.com/chrome/src-internal/+/2f5601601a8a5d6fd4219bed476b6ca5d0728e52
memory:chrome:all_processes:reported_by_os:proportional_resident_size: 1.077e+08 → 1.043e+08 (-3.476e+06)

Understanding performance regressions:
  http://g.co/ChromePerformanceRegressions

So the reason for the improvement is on Dec 12th is:

2018-12-10 clank-buildbot@google.com Update Orderfile.
https://chrome-internal.googlesource.com/clank/internal/apps.git/+/01993c05e782a2bc2e5807a2402c856cad0fd034

+pasko FYI - do you know what was the work that enabled this improvement?

roughly aligns with 04f4103842f32cee0b6206b96797a1b622642f60, the amount is also according to expectations

oops, sent the message too early ..

Thank you, Juan for nailing it with a bisect!