All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=766511

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=1228182fefa9396749a402e1f045424bb8aee6e1090aa4212246f604df94f2d8


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

chromium-rel-win7-gpu-ati

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8968031508692270304

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

Hi reed@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 : Mike Reed
  Commit : 7a542c559a6e584107b94e6254ac3c7f9f24b591
  Date   : Tue Apr 11 16:38:17 2017
  Subject: Change bitmapcache to not rely on lockpixels.

Bisect Details
  Configuration: winx64ati_perf_bisect
  Benchmark    : image_decoding.image_decoding_measurement
  Metric       : ImageDecoding_avg/ImageDecoding_avg
  Change       : 7.83% | 42.226225 -> 45.5312333333

Revision                             Result                   N
chromium@463673                      42.2262 +- 0.550289      6      good
chromium@463686                      42.2916 +- 0.379181      6      good
chromium@463693                      42.4169 +- 0.44086       6      good
chromium@463694                      42.2261 +- 0.2587        6      good
chromium@463694,skia@77443974ea      42.3221 +- 0.607453      6      good
chromium@463694,skia@7a542c559a      44.6984 +- 0.220618      6      bad       <--
chromium@463695                      44.8741 +- 0.389836      6      bad
chromium@463696                      44.9256 +- 0.299788      6      bad
chromium@463699                      44.789 +- 0.401368       6      bad
chromium@463724                      45.5312 +- 0.353526      6      bad

To Run This Test
  src/tools/perf/run_benchmark -v --browser=release_x64 --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests image_decoding.image_decoding_measurement

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8968031508692270304


For feedback, file a bug with component Speed>Bisection

WontFix-ing as this benchmark has been replaced.