The log contains

[84700:44659:0628/095203:784992388770835:ERROR:vt_video_decode_accelerator_mac.cc(695)] CMBlockBufferCreateWithMemoryBlock(): Error Domain=NSOSStatusErrorDomain Code=-12704 "(null)" (-12704)

after which the pipeline stops due to a decoding error.

It seems that YouTube is not always seeking to keyframes, and so this decode error is somewhat expected.

I was able to reliably trigger the behavior with https://www.youtube.com/watch?v=nh0ac5HUpDU and then seeking to 1:08 (via "$('video').currentTime = 68").

I have created a CL to make VTVDA more robust against this case, but I'm assigning the bug over to Matt to investigate if there is a Chrome bug causing the incorrect seek.

The demuxers should always start returning frames from a keyframe.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/fcd0ee541d7f3f74171f194dcc86cb1672a33139

commit fcd0ee541d7f3f74171f194dcc86cb1672a33139
Author: sandersd <sandersd@chromium.org>
Date: Wed Jun 29 17:36:22 2016

VTVDA: Handle more missing IDR situations.

This CL reduces the conditions on dropping frames to just
|waiting_for_idr_|. We don't need to consider whether there is a pending
config change (this should be a decode error if we are not waiting) or
whether |session_| is set (|waiting_for_idr_| covers this).

BUG= 623892 

Review-Url: https://codereview.chromium.org/2101183004
Cr-Commit-Position: refs/heads/master@{#402853}

[modify] https://crrev.com/fcd0ee541d7f3f74171f194dcc86cb1672a33139/media/gpu/vt_video_decode_accelerator_mac.cc

Your change meets the bar and is auto-approved for M52 (branch: 2743)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/34efc858465acf3180451339c3727b513f43b7d9

commit 34efc858465acf3180451339c3727b513f43b7d9
Author: Dan Sanders <sandersd@chromium.org>
Date: Thu Jun 30 18:51:49 2016

Merge to M52: VTVDA: Handle more missing IDR situations.

This CL reduces the conditions on dropping frames to just
|waiting_for_idr_|. We don't need to consider whether there is a pending
config change (this should be a decode error if we are not waiting) or
whether |session_| is set (|waiting_for_idr_| covers this).

BUG= 623892 

Review-Url: https://codereview.chromium.org/2101183004
Cr-Commit-Position: refs/heads/master@{#402853}
(cherry picked from commit fcd0ee541d7f3f74171f194dcc86cb1672a33139)

Review URL: https://codereview.chromium.org/2115643002 .

Cr-Commit-Position: refs/branch-heads/2743@{#550}
Cr-Branched-From: 2b3ae3b8090361f8af5a611712fc1a5ab2de53cb-refs/heads/master@{#394939}

[modify] https://crrev.com/34efc858465acf3180451339c3727b513f43b7d9/media/gpu/vt_video_decode_accelerator_mac.cc

 Issue 626642  has been merged into this issue.

=> sandersd@

It seems like further work on this is probably best tracked by  bug 584384 . If you agree, please duplicate this into that bug. Thanks!