All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=776039

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=653ea203b6fab40bb7cc435d332c29024c25d6f50d82693d42973666376d74c9


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

android-nexus6

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8965370820897964048

=== BISECT JOB RESULTS ===
Bisect was unable to run to completion

Error: INFRA_FAILURE

The bisect was able to narrow the range, you can try running with:
  good_revision: b4de8997256ede9e6df51e2bf941dab9e47cd193
  bad_revision : c16ce88057b6cc5117d9577ca510e8f41617e701

If failures persist contact the team (see below) and report the error.


Bisect Details
  Configuration: android_nexus6_perf_bisect
  Benchmark    : blink_perf.bindings
  Metric       : get-attribute/get-attribute

Revision             Result                   N
chromium@508045      66.8908 +- 4.12923       6      good
chromium@508062      58.9699 +- 6.79066       6      bad
chromium@508079      52.6005 +- 1.55727       6      bad
chromium@508113      55.2327 +- 0.591835      6      bad
chromium@508181      55.8263 +- 1.03501       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-chromium --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests blink_perf.bindings

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8965370820897964048


For feedback, file a bug with component Speed>Bisection

Started bisect job https://chromeperf.appspot.com/buildbucket_job_status/8965342786320272128

Trying a bisect with a wider range, not sure if the previous bisect fully reproduced what happened on the graph.

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

Hi keishi@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 : Keishi Hattori
  Commit : b092fa9950a914b79d01ad59e6ec3f9c8e18b0db
  Date   : Thu Oct 12 05:00:26 2017
  Subject: Revert "Abstrating file access operation in zip creation."

Bisect Details
  Configuration: android_nexus6_perf_bisect
  Benchmark    : blink_perf.bindings
  Metric       : get-attribute/get-attribute
  Change       : 15.36% | 60.1865017474 -> 50.9705209092

Revision             Result                   N
chromium@507922      60.1865 +- 6.01129       6       good
chromium@508091      56.1793 +- 1.59458       6       good
chromium@508175      55.974 +- 1.4361         6       good
chromium@508217      55.8704 +- 2.82573       6       good
chromium@508238      54.1732 +- 2.44876       14      good
chromium@508249      52.8609 +- 5.34744       14      good
chromium@508254      52.9454 +- 1.76592       6       good
chromium@508255      52.8777 +- 0.702918      6       good
chromium@508256      50.7546 +- 2.6811        6       bad       <--
chromium@508257      49.7969 +- 2.87475       6       bad
chromium@508259      50.9705 +- 3.41028       14      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-chromium --output-format=chartjson --upload-results --pageset-repeat=1 --also-run-disabled-tests blink_perf.bindings

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

Debug information about this bisect:
  https://chromeperf.appspot.com/buildbucket_job_status/8965342786320272128


For feedback, file a bug with component Speed>Bisection

WontFix-ing because this is a pretty narrowly scoped bug, and if this CL is the cuplrit (bisect data shows a lot of noise) it's a revert.