Bisect here:
https://chromeperf.appspot.com/buildbucket_job_status/9015398770222529232

===== BISECT JOB RESULTS =====
Status: completed


===== SUSPECTED CL(s) =====
Subject : UTF-8 detector for pages missing encoding info
Author  : jinsukkim
Commit description:
  
Experiment crbug.com/518968 shows that about 30% of the pages
missing character encoding information are encoded in UTF-8.
This CL runs a quick one-pass scan against them to check if
they are encoded in UTF-8. It helps get the encoding right
for 30% of the pages without having to turn on full auto-encoding
detection logic which is disabled due to slow performance.

BUG= 583549 
TEST=Layout test: fast/encoding/unlabelled-non-ascii-utf8.html

Review URL: https://codereview.chromium.org/1721373002

Cr-Commit-Position: refs/heads/master@{#387209}
Commit  : 2af3917eb9ca14b263116d664a8257ae69680610
Date    : Thu Apr 14 02:26:47 2016


===== TESTED REVISIONS =====
Revision                Exit Code   Std. Dev.   Num Values  Good?
chromium@387061         0           N/A         2           good
chromium@387151         0           N/A         2           good
chromium@387195         0           N/A         2           good
chromium@387207         0           N/A         2           good
chromium@387208         0           N/A         2           good
chromium@387209         1           N/A         2           bad         <-
chromium@387210         1           N/A         2           bad
chromium@387212         1           N/A         2           bad
chromium@387216         1           N/A         2           bad
chromium@387240         1           N/A         2           bad

Bisect job ran on: mac_hdd_perf_bisect
Bug ID: 603560

Test Command: src/tools/perf/run_benchmark -v --browser=release --output-format=chartjson --also-run-disabled-tests octane
Test Metric: Box2D/Box2D
Relative Change: Zero to non-zero
Score: 99.9

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/mac_hdd_perf_bisect/builds/483
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9015398770222529232


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  https://chromeperf.appspot.com/bad_bisect?try_job_id=603560

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