All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=641083

Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?keys=agxzfmNocm9tZXBlcmZyFAsSB0Fub21hbHkYgICgvrjqogoM


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

chromium-rel-win8-dual

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/9003330872150371920

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

Hi xiaochengh@chromium.org, the bisect results pointed to your CL below as possibly
causing a regression. Please have a look at this info and see whether
your CL be related.


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


===== SUSPECTED CL(s) =====
Subject : Stop SpellChecker::chunkAndMarkAllMisspellingsAndBadGrammar from using TextCheckingParagrah
Author  : xiaochengh
Commit description:
  
SpellChecker::chunkAndMarkAllMisspellingsAndBadGrammar() does not really need
a TextCheckingParagraph as its parameter; an EphemeralRange of text to check is
sufficient.

Hence, this patch changes its parameter from a TextCheckingParagraph to an
EphemeralRange, simplifying code and improving performance by eliminating the
overhead for finding the paragraph containing the text to be checked.

BUG=n/a
TEST=n/a; no visible change

Review-Url: https://codereview.chromium.org/2273453003
Cr-Commit-Position: refs/heads/master@{#414328}
Commit  : 41165826c11cc0b7f1457b4c455d7e2eb2de0819
Date    : Thu Aug 25 05:42:11 2016


===== TESTED REVISIONS =====
Revision         Mean     Std Dev     N  Good?
chromium@414310  1.67243  0.00613843  5  good
chromium@414325  1.69024  0.00170011  5  good
chromium@414327  1.68754  0.00115666  5  good
chromium@414328  1.41879  0.00232319  5  bad    <--
chromium@414329  1.42928  0.00222411  5  bad
chromium@414332  1.41047  0.00358295  5  bad
chromium@414339  1.41751  0.00162184  5  bad

Bisect job ran on: win_8_perf_bisect
Bug ID: 641083

Test Command: src/tools/perf/run_benchmark -v --browser=release --output-format=chartjson --upload-results --also-run-disabled-tests blink_perf.dom
Test Metric: textarea-edit/textarea-edit
Relative Change: 15.24%
Score: 99.9

Buildbot stdio: http://build.chromium.org/p/tryserver.chromium.perf/builders/win_8_perf_bisect/builds/2153
Job details: https://chromeperf.appspot.com/buildbucket_job_status/9003330872150371920


Not what you expected? We'll investigate and get back to you!
  https://chromeperf.appspot.com/bad_bisect?try_job_id=5219110170918912

| O O | Visit http://www.chromium.org/developers/speed-infra/perf-bug-faq
|  X  | for more information addressing perf regression bugs. For feedback,
| / \ | file a bug with component Tests>AutoBisect.  Thank you!

I'll revert my CL and investigate.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/081b3356bbea770e05fa19c2947e67b9916b5786

commit 081b3356bbea770e05fa19c2947e67b9916b5786
Author: xiaochengh <xiaochengh@chromium.org>
Date: Fri Aug 26 08:57:34 2016

Revert "Stop SpellChecker::chunkAndMarkAllMisspellingsAndBadGrammar from using TextCheckingParagrah"

This is a manual revert of commit 41165826c11cc0b7f1457b4c455d7e2eb2de0819,
due to causing performance regression.

Original issue's description:
> Stop SpellChecker::chunkAndMarkAllMisspellingsAndBadGrammar from using TextCheckingParagrah
>
> SpellChecker::chunkAndMarkAllMisspellingsAndBadGrammar() does not really need
> a TextCheckingParagraph as its parameter; an EphemeralRange of text to check is
> sufficient.
>
> Hence, this patch changes its parameter from a TextCheckingParagraph to an
> EphemeralRange, simplifying code and improving performance by eliminating the
> overhead for finding the paragraph containing the text to be checked.
>
> BUG=n/a
> TEST=n/a; no visible change
>
> Committed: https://crrev.com/41165826c11cc0b7f1457b4c455d7e2eb2de0819
> Cr-Commit-Position: refs/heads/master@{#414328}

BUG= 641083 
TBR=yosin@chromium.org

Review-Url: https://codereview.chromium.org/2286573002
Cr-Commit-Position: refs/heads/master@{#414675}

[modify] https://crrev.com/081b3356bbea770e05fa19c2947e67b9916b5786/third_party/WebKit/Source/core/editing/spellcheck/SpellChecker.cpp
[modify] https://crrev.com/081b3356bbea770e05fa19c2947e67b9916b5786/third_party/WebKit/Source/core/editing/spellcheck/SpellChecker.h