All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=774090

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=864a404bfcadb5bf82f5b361f53258d3fc6b8f4cd2edebee08020ecf071b99d9


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

android-nexus7v2
android-webview-nexus5X
android-webview-nexus6

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8965932541406803456

=== Auto-CCing suspected CL author robertphillips@google.com ===

Hi robertphillips@google.com, 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 : Robert Phillips
  Commit : c7e66ea989006b6f21ccf4e4c33644a55b5455ec
  Date   : Mon Oct 09 18:07:34 2017
  Subject: Disable deferred proxies a different way in Chrome

Bisect Details
  Configuration: android_webview_nexus6_aosp_perf_bisect
  Benchmark    : thread_times.key_silk_cases
  Metric       : thread_raster_cpu_time_per_frame/http___jsfiddle.net_xLuvC_1_show_
  Change       : 41.02% | 17.6044128617 -> 24.8261731304

Revision                             Result                   N
chromium@507638                      17.6044 +- 0.618011      6      good
chromium@507651                      17.5265 +- 0.821288      6      good
chromium@507657                      17.6699 +- 0.473263      6      good
chromium@507660                      17.7321 +- 1.23825       6      good
chromium@507662                      17.6466 +- 0.980334      6      good
chromium@507662,skia@32a6924162      17.9335 +- 0.729895      6      good
chromium@507662,skia@c7e66ea989      25.0447 +- 0.650954      6      bad       <--
chromium@507662,skia@37387c80cc      24.46 +- 0.625296        6      bad
chromium@507662,skia@c4b015ad5f      24.6399 +- 0.501767      6      bad
chromium@507662,skia@df007e1a7a      24.6812 +- 0.959501      6      bad
chromium@507663                      24.8262 +- 0.511873      6      bad

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 --story-filter=http...jsfiddle.net.xLuvC.1.show. thread_times.key_silk_cases

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8965932541406803456


For feedback, file a bug with component Speed>Bisection

 Issue 774092  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a92fe336f8d823fa96c5916508303f10ce30629e

commit a92fe336f8d823fa96c5916508303f10ce30629e
Author: Robert Phillips <robertphillips@google.com>
Date: Tue Oct 31 20:36:30 2017

Reenable Skia's deferred proxies

Bug:  774090 ,  769898 ,  769760 
Change-Id: Id6ddfa82a2c16da476b2caaa93d5d3cd99aaedc8
Reviewed-on: https://chromium-review.googlesource.com/744683
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Brian Salomon <bsalomon@chromium.org>
Cr-Commit-Position: refs/heads/master@{#512944}
[modify] https://crrev.com/a92fe336f8d823fa96c5916508303f10ce30629e/skia/config/SkUserConfig.h
[modify] https://crrev.com/a92fe336f8d823fa96c5916508303f10ce30629e/third_party/WebKit/LayoutTests/platform/mac/virtual/gpu-rasterization/images/color-profile-background-image-cross-fade-expected.png
[modify] https://crrev.com/a92fe336f8d823fa96c5916508303f10ce30629e/third_party/WebKit/LayoutTests/platform/mac/virtual/gpu-rasterization/images/color-profile-background-image-cross-fade-png-expected.png
[modify] https://crrev.com/a92fe336f8d823fa96c5916508303f10ce30629e/third_party/WebKit/LayoutTests/platform/mac/virtual/gpu-rasterization/images/color-profile-mask-image-svg-expected.png
[modify] https://crrev.com/a92fe336f8d823fa96c5916508303f10ce30629e/third_party/WebKit/LayoutTests/platform/win/virtual/gpu-rasterization/images/color-profile-background-image-cross-fade-expected.png
[modify] https://crrev.com/a92fe336f8d823fa96c5916508303f10ce30629e/third_party/WebKit/LayoutTests/platform/win/virtual/gpu-rasterization/images/color-profile-background-image-cross-fade-png-expected.png
[modify] https://crrev.com/a92fe336f8d823fa96c5916508303f10ce30629e/third_party/WebKit/LayoutTests/platform/win/virtual/gpu-rasterization/images/color-profile-mask-image-svg-expected.png

Skia's deferred proxies were re-enabled in the CL in #5 and it appears that the majority of the perf regressions have been resolved.

I don't really know why the two metrics that didn't resolve themselves:

thread_raster_cpu_time_per_frame
thread_IO_cpu_time_per_frame

every regressed since the causal CL was GPU-only.