All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=787772

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=7700fccf36d010601e77234a88130148af008d69b9d90e90e7ab0932901b967a


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

android-webview-nexus6

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8962230094727064704

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

Hi zakerinasab@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 : Reza.Zakerinasab
  Commit : ec67cae3b77ca0f9d641a2722d8d1f6090b346fd
  Date   : Mon Nov 20 17:54:39 2017
  Subject: With {premultiplyAlpha: "none"} ImageBitmap should avoid premul code path

Bisect Details
  Configuration: android_webview_nexus6_aosp_perf_bisect
  Benchmark    : blink_perf.canvas
  Metric       : createImageBitmapFromImageData/createImageBitmapFromImageData
  Change       : 10.48% | 54.0545952453 -> 48.3873781981

Revision             Result                   N
chromium@517822      54.0546 +- 1.36053       6      good
chromium@517840      53.9206 +- 1.29571       6      good
chromium@517849      53.8255 +- 1.78218       6      good
chromium@517854      53.7751 +- 0.740029      6      good
chromium@517856      53.9424 +- 1.19645       6      good
chromium@517857      53.6958 +- 1.33042       6      good
chromium@517858      48.3874 +- 1.00334       6      bad       <--

Please refer to the following doc on diagnosing blink_perf regressions:
  https://chromium.googlesource.com/chromium/src/+/master/docs/speed/benchmark_harnesses/blink_perf.md

To Run This Test
  src/tools/perf/run_benchmark -v --browser=android-webview --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests blink_perf.canvas

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8962230094727064704


For feedback, file a bug with component Speed>Bisection

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/02dbe866ad7f51475007f46673253ed934179529

commit 02dbe866ad7f51475007f46673253ed934179529
Author: Reza.Zakerinasab <zakerinasab@chromium.org>
Date: Mon Dec 04 21:55:48 2017

Address canvas perf regressions in createImageBitmapFromImageData

This change tries to address the perf regression reported for
createImageBitmapFromImageData canvas perf test. This change performs
the premul operation in ImageData in advance, instead of doing that after
creating the ImageBitmap. This has resulted in ~60% perf improvement
on the local Linux machine, so it hopefully must address the regressions.

Bug:  782813 , 787772 , 787811 
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
Change-Id: If0f02d99677348d49cc9d16e910113b4250afb69
Reviewed-on: https://chromium-review.googlesource.com/802855
Reviewed-by: Justin Novosad <junov@chromium.org>
Commit-Queue: Mohammad Reza Zakerinasab <zakerinasab@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521476}
[modify] https://crrev.com/02dbe866ad7f51475007f46673253ed934179529/third_party/WebKit/Source/core/html/ImageData.cpp
[modify] https://crrev.com/02dbe866ad7f51475007f46673253ed934179529/third_party/WebKit/Source/core/html/ImageData.h
[modify] https://crrev.com/02dbe866ad7f51475007f46673253ed934179529/third_party/WebKit/Source/core/imagebitmap/ImageBitmap.cpp
[modify] https://crrev.com/02dbe866ad7f51475007f46673253ed934179529/third_party/WebKit/Source/core/imagebitmap/ImageBitmap.h
[modify] https://crrev.com/02dbe866ad7f51475007f46673253ed934179529/third_party/WebKit/Source/platform/graphics/GraphicsTypes.h