All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=616942

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgnO6mrAoM


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

android-nexus6

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


===== SUSPECTED CL(s) =====
Subject : Track DisplayItemClient aliveness for each PaintController
Author  : wangxianzhu
Commit description:
  
After CHECK_DISPLAY_ITEM_CLIENT_ALIVENESS was enabled, we didn't get
crashes in DisplayItemClient::~DisplayItemClient() when the
DisplayItemClient should be alive. We still get crashes in
PaintController::updateCacheGeneration() [1]
which indicates that we still have short-lived DisplayItemClient but
not catched by aliveness checking. This might happen if there are
multiple PaintControllers (e.g. one created by SkPictureBuilder and
another by GraphicsLayer).

Separately track DisplayItemClient aliveness for each PaintController
in order to catch the issue.

[1] https://crash.corp.google.com/browse?q=custom_data.ChromeCrashProto.ptype%3D%27renderer%27%20AND%20custom_data.ChromeCrashProto.magic_signature_1.name%20like%20%27blink%3A%3APaintController%3A%3A%25%27%20AND%20product.version%3D%2753.0.2751.0%27&ignore_case=false&enable_rewrite=true&omit_field_name=&omit_field_value=&omit_field_opt=%3D&stbtiq=&reportid=20bc8a5c00000000&index=2#4

BUG=609218

Review-Url: https://codereview.chromium.org/2031623002
Cr-Commit-Position: refs/heads/master@{#397243}
Commit  : 53559da8fd5faa99d30a00eadbc6da3aebbde2b1
Date    : Wed Jun 01 21:16:57 2016


===== TESTED REVISIONS =====
Revision         Mean     Std Dev    N   Good?
chromium@397237  16.8947  0.0403411  8   good
chromium@397242  16.8837  0.0255805  12  good
chromium@397243  17.0222  0.100033   12  bad    <--
chromium@397244  16.9675  0.0777148  12  bad
chromium@397246  17.0104  0.0566937  12  bad
chromium@397255  17.0355  0.0689182  8   bad
chromium@397273  17.0764  0.0971     8   bad

Bisect job ran on: android_nexus6_perf_bisect
Bug ID: 616942

Test Command: src/tools/perf/run_benchmark -v --browser=android-chromium --output-format=chartjson --upload-results --also-run-disabled-tests smoothness.sync_scroll.key_mobile_sites_smooth
Test Metric: frame_times/http___mobile-news.sandbox.google.com_news_pt0
Relative Change: 0.83%
Score: 99.5

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus6_perf_bisect/builds/2211
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9010926732530997472


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  https://chromeperf.appspot.com/bad_bisect?try_job_id=5906875694972928

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