How is this a regression? What is actually broken?

Can you be more specific about where you saw the the error? https://build.chromium.org/p/chromium.win/builders/Win10%20Tests%20x64 has 2000+ test runs and each test run is currently 200+ steps. Are you talking about https://build.chromium.org/p/chromium.win/builders/Win10%20Tests%20x64/builds/2494/steps/browser_tests%20on%20Windows-10-10586/logs/DevToolsSanityTest.TestWindowInitializedOnNavigateBack ?? I only found it because it is the most recent red test run. In a few days, I wouldn't be able to guess what you are referring to.

----
[ RUN      ] DevToolsSanityTest.TestWindowInitializedOnNavigateBack
[140:1168:0714/024126:ERROR:dxva_video_decode_accelerator_win.cc(222)] Error in dxva_video_decode_accelerator_win.cc on line 404
[6492:376:0714/024126:INFO:CONSOLE(3)] "239", source: chrome://dummyurl/ (3)
[6492:376:0714/024127:INFO:CONSOLE(3)] "239", source: chrome://dummyurl/ (3)
[6492:376:0714/024127:INFO:CONSOLE(3)] "239", source: chrome://dummyurl/ (3)
c:uild\slave\win_x64_builderuild\src\chromerowser\devtools\devtools_sanity_browsertest.cc(141): error: Value of: result
  Actual: "[FAILED] Expected: '1', but was '0'"
Expected: "[OK]"
[  FAILED  ] DevToolsSanityTest.TestWindowInitializedOnNavigateBack, where TypeParam =  and GetParam() =  (1249 ms)
----

The failure is in devtools_sanity_browsertest.cc. Is that a concern? Did you file a bug for that? Is this concern specifically about the dxva ERROR logging?

All I did is do some generic refactoring. The code is in media/gpu/dxva_video_decode_accelerator_win.cc, surely media/gpu/OWNERS is a better set of owners? I know next to nothing about DXVA.

Sorry if my analysis and triage was bad here.

I found these issues reported:
https://luci-logdog.appspot.com/v/?s=chromium%2Fbb%2Fchromium.win%2FWin10_Tests_x64%2F2494%2F%2B%2Frecipes%2Fsteps%2Fbrowser_tests_on_Windows-10-10586%2F0%2Flogs%2FDevToolsSanityTest.TestWindowInitializedOnNavigateBack%2F0

where one failure was e.g.

DevToolsSanityTest.TestWindowInitializedOnNavigateBack (run #1):
[ RUN      ] DevToolsSanityTest.TestWindowInitializedOnNavigateBack
[140:1168:0714/024126:ERROR:dxva_video_decode_accelerator_win.cc(222)] Error in dxva_video_decode_accelerator_win.cc on line 404
[6492:376:0714/024126:INFO:CONSOLE(3)] "239", source: chrome://dummyurl/ (3)
[6492:376:0714/024127:INFO:CONSOLE(3)] "239", source: chrome://dummyurl/ (3)
[6492:376:0714/024127:INFO:CONSOLE(3)] "239", source: chrome://dummyurl/ (3)
c:uild\slave\win_x64_builderuild\src\chromerowser\devtools\devtools_sanity_browsertest.cc(141): error: Value of: result
  Actual: "[FAILED] Expected: '1', but was '0'"
Expected: "[OK]"

So, yes, I could have linked that to the DevToolsSanityTest instead. Agree.

But I recalled having seen the same log of:

[140:1168:0714/024126:ERROR:dxva_video_decode_accelerator_win.cc(222)] Error in dxva_video_decode_accelerator_win.cc on line 404

earlier today in other tests as well hence checked the history of dxva_video_decode_accelerator_win.cc and found:

https://chromium.googlesource.com/chromium/src/+log/a74ad2baef4dcd2d432fb1241661f9577a08acca/media/gpu/dxva_video_decode_accelerator_win.cc

I realize now that your change is not causing this and I should not have assigned the issue to you.

I will see if I can find more failing tests with the same error message and link to this issue.

Also adding kozyatinskiy@ who has done work on the DevToolsSanityTest tests.

The test flaked again: https://build.chromium.org/p/chromium.win/builders/Win10%20Tests%20x64/builds/2885, https://build.chromium.org/p/chromium.win/builders/Win10%20Tests%20x64/builds/2890, stdio attached. I will disable it on Win.

Deleted: Log File contents.html 409 KB

Log File contents.html 409 KB View Download

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4d9b40394ca4513694f5edc38d7aac36d4ba4cc7

commit 4d9b40394ca4513694f5edc38d7aac36d4ba4cc7
Author: vabr <vabr@chromium.org>
Date: Tue Jul 26 15:56:18 2016

Disable DevToolsSanityTest.TestWindowInitializedOnNavigateBack on Win

The test flakes on Win, more info on  http://crbug.com/628174#c4 .
TBR=dgozman@chromium.org
BUG= 628174 

Review-Url: https://codereview.chromium.org/2184633003
Cr-Commit-Position: refs/heads/master@{#407815}

[modify] https://crrev.com/4d9b40394ca4513694f5edc38d7aac36d4ba4cc7/chrome/browser/devtools/devtools_sanity_browsertest.cc

 Issue 655959  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/db4bad9dbc1e279b72e9c08f53d0429613e5d520

commit db4bad9dbc1e279b72e9c08f53d0429613e5d520
Author: kozyatinskiy <kozyatinskiy@chromium.org>
Date: Fri Oct 14 15:49:51 2016

[DevTools] disabled DevToolsSanityTest.TestWindowInitializedOnNavigateBack

BUG= chromium:628174 
TBR=dgozman@chromium.org

Review-Url: https://codereview.chromium.org/2420923002
Cr-Commit-Position: refs/heads/master@{#425335}

[modify] https://crrev.com/db4bad9dbc1e279b72e9c08f53d0429613e5d520/chrome/browser/devtools/devtools_sanity_browsertest.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9b0d8b18dc95b8b40c19822b11fe1ed0e743ae38

commit 9b0d8b18dc95b8b40c19822b11fe1ed0e743ae38
Author: Alexey Kozyatinskiy <kozyatinskiy@chromium.org>
Date: Wed Jan 03 18:34:57 2018

[DevTools] unflake TestWindowInitializedOnNavigateBack

TBR=dgozman@chromium.org

Bug:  chromium:628174 
Change-Id: Ibee6850f5f58296eec80097dc2c74aa1237a6c31
Reviewed-on: https://chromium-review.googlesource.com/848321
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#526751}
[modify] https://crrev.com/9b0d8b18dc95b8b40c19822b11fe1ed0e743ae38/chrome/browser/devtools/devtools_sanity_browsertest.cc
[modify] https://crrev.com/9b0d8b18dc95b8b40c19822b11fe1ed0e743ae38/third_party/WebKit/Source/devtools/front_end/Tests.js