All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=774911

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=aa36f283f8f9d77719c142733ebbf5ff2c509c2544fa458d3d5c770d3b4d490c


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

android-nexus5X

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8965605462365043936

=== Auto-CCing suspected CL author adithyas@chromium.org ===

Hi adithyas@chromium.org, the bisect results pointed to your CL, please take a look at the
results.


=== BISECT JOB RESULTS ===
Perf regression found with culprit

Suspected Commit
  Author : Adithya Srinivasan
  Commit : 0e9f822a3530e2ae97d0d04e80178ef6a356f24a
  Date   : Wed Oct 11 13:48:42 2017
  Subject: Enable Blink RCS for v8.runtimestats.browsing_mobile

Bisect Details
  Configuration: android_nexus5X_perf_bisect
  Benchmark    : v8.runtimestats.browsing_mobile
  Metric       : Total:duration_avg/browse_chrome/browse_chrome_newtab
  Change       : 6.25% | 10270.6201667 -> 10912.6476667

Revision             Result                  N
chromium@507922      10270.6 +- 215.078      6      good
chromium@507952      10328.7 +- 73.6443      6      good
chromium@507967      10380.1 +- 145.038      6      good
chromium@507968      10415.8 +- 226.695      6      good
chromium@507969      10962.0 +- 129.441      6      bad       <--
chromium@507971      10992.4 +- 138.426      6      bad
chromium@507974      10935.9 +- 259.992      6      bad
chromium@507981      10912.6 +- 41.5316      6      bad

To Run This Test
  src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests --story-filter=browse.chrome.newtab v8.runtimestats.browsing_mobile

More information on addressing performance regressions:
  http://g.co/ChromePerformanceRegressions

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8965605462365043936


For feedback, file a bug with component Speed>Bisection

That CL enables Blink runtime call stats for the browsing_mobile benchmark (for better attribution inside blink). Measuring call stats in Blink does have overhead, but it is disabled by default, so this isn't a real performance regression.