All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=806238

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=6b39b4563b6caa7e959bb68828c05a4a433f210c8b54249a0f2589fa24542749


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

chromium-rel-mac-retina
chromium-rel-mac11-air

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/12a4fe22840000

📍 Found a significant difference after 1 commit.
https://pinpoint-dot-chromeperf.appspot.com/job/12a4fe22840000

Rewrite WebContentsVideoCaptureDevice, to use new VIZ-based capture impl
By miu@chromium.org · Thu Jan 25 02:23:58 2018
chromium @ 77e19b91361effda2f4eb9f278d9e038aca58d7c

Understanding performance regressions:
  http://g.co/ChromePerformanceRegressions

This could actually be a missing trace event somewhere in the new impl. Seems to affect all Mac platforms ( bug 806226  is a duplicate).

 Issue 806226  has been merged into this issue.

Wrapping up a project soon, will turn my attention fully to tab capture performance issues in the beginning of June. This bug looks like the new code just broke the trace. But, it's not clear why this only affected Mac Air.

The NextAction date has arrived: 2018-06-04

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c9cee7e5db8b778279bf39c3a249ab1140616b83

commit c9cee7e5db8b778279bf39c3a249ab1140616b83
Author: Yuri Wiitala <miu@chromium.org>
Date: Tue Oct 30 21:46:17 2018

Get performance_browser_tests working again.

Fixes:

1. The timestamp field in the event traces has been made consistent
(between the Capture and OnBufferReceived trace events). This allows
pipeline tracking of individual frames (and fixes the 97-100% drop rate
bug).

2. Add BUILD.gn target dependencies to build browser PAK/resources that
are required in order to run the binary.

3. Allow thread-blocking in media::cast::test::UDPProxyImpl.

Bug:  789192 ,  816466 ,  806238 
Change-Id: If606989e8ea5eea34fd25e58246ecb7dd9cb75d1
Reviewed-on: https://chromium-review.googlesource.com/c/1308103
Reviewed-by: Takumi Fujimoto <takumif@chromium.org>
Commit-Queue: Yuri Wiitala <miu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#604023}
[modify] https://crrev.com/c9cee7e5db8b778279bf39c3a249ab1140616b83/chrome/browser/extensions/api/cast_streaming/performance_test.cc
[modify] https://crrev.com/c9cee7e5db8b778279bf39c3a249ab1140616b83/chrome/test/BUILD.gn
[modify] https://crrev.com/c9cee7e5db8b778279bf39c3a249ab1140616b83/components/viz/service/frame_sinks/video_capture/frame_sink_video_capturer_impl.cc
[modify] https://crrev.com/c9cee7e5db8b778279bf39c3a249ab1140616b83/media/cast/test/utility/udp_proxy.cc