All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=905196

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=93752038ab585e171b1b4278fd163430058891307d3fe3affddcaad1207ee11d


Bot(s) for this bug's original alert(s):

mac-10_13_laptop_high_end-perf

blink_perf.shadow_dom - Benchmark documentation link:
  https://bit.ly/blink-perf-benchmarks

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/112652e3e40000

📍 Found a significant difference after 1 commit.
https://pinpoint-dot-chromeperf.appspot.com/job/112652e3e40000

Add assigned_nodes_index_ map for slot's assigned child by rakina@chromium.org
https://chromium.googlesource.com/chromium/src/+/eaddcb2899f1120b8a8d4d30d3c2a2911e65d049
v1-large-shallow-distribution: 1.18 → 1.443 (+0.2625)

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

Benchmark documentation link:
  https://bit.ly/blink-perf-benchmarks

This can be a perf regression. P2 -> P1.

 Issue 905197  has been merged into this issue.

hayato@, is this regression fixed by your recent Flat tree traversal CLs?

Yes, as far as I can read from the graph, my CL [1] fixed the regression caused by this CL [2].

- [1] https://chromium-review.googlesource.com/c/chromium/src/+/1337225
- [2] https://chromium-review.googlesource.com/c/chromium/src/+/1328622