All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=918630

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=922742ead23d0031478988926e19e610e2073d1e1be489b893b25e4fb05ce503


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

android-nexus5x-perf

rendering.mobile - Benchmark documentation link:
  https://bit.ly/rendering-benchmarks

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/1651453c940000

📍 Found a significant difference after 1 commit.
https://pinpoint-dot-chromeperf.appspot.com/job/1651453c940000

Add SequenceManager to field trial testing config by carlscab@google.com
https://chromium.googlesource.com/chromium/src/+/84ecbf7c0b1eca668dba1471a50f065c6d558737
tasks_per_frame_total_all: 696.7 → 1660 (+963.4)

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

Benchmark documentation link:
  https://bit.ly/rendering-benchmarks

I think we can ignore this for now.  It's possible there are more tasks due to the way the ThreadControllerWithMessagePumpImpl interfaces with the MessagePump. Later we will merge the DoImmediateWord and DoDelayedWork which would solve that.

Yeah, looks the same as crbug.com/915832