The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4c62d2e2886895da00de3dcade7f6dfc6abd8e61

commit 4c62d2e2886895da00de3dcade7f6dfc6abd8e61
Author: Mounir Lamouri <mlamouri@chromium.org>
Date: Wed Feb 07 15:48:21 2018

Autoplay: improve error messages to include links to documentation.

This is also creating new error messages that we did not use to fire
and give more information about what happened.

Bug:  807646 
Change-Id: I42f6cd269fac4deda3c632fcf7a67142fe1863df
Reviewed-on: https://chromium-review.googlesource.com/895308
Commit-Queue: Mounir Lamouri <mlamouri@chromium.org>
Reviewed-by: Tommy Steimel <steimel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#535009}
[modify] https://crrev.com/4c62d2e2886895da00de3dcade7f6dfc6abd8e61/third_party/WebKit/LayoutTests/http/tests/media/autoplay/document-user-activation-navigation-nogesture-expected.txt
[modify] https://crrev.com/4c62d2e2886895da00de3dcade7f6dfc6abd8e61/third_party/WebKit/Source/core/html/media/AutoplayPolicy.cpp
[modify] https://crrev.com/4c62d2e2886895da00de3dcade7f6dfc6abd8e61/third_party/WebKit/Source/core/html/media/AutoplayPolicy.h
[modify] https://crrev.com/4c62d2e2886895da00de3dcade7f6dfc6abd8e61/third_party/WebKit/Source/core/html/media/HTMLMediaElement.cpp

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/488dc7f72001e12a112c2ebb074bd33a19bbee0b

commit 488dc7f72001e12a112c2ebb074bd33a19bbee0b
Author: Mounir Lamouri <mlamouri@chromium.org>
Date: Fri Feb 09 12:31:01 2018

Autoplay: improve console messages when AudioContext can't start.

This is adding a link to an article with more details.

Bug:  807646 
Change-Id: I68ce94a702d48239e5fed20538ef5f24d7dc6a7f
Reviewed-on: https://chromium-review.googlesource.com/908458
Commit-Queue: Mounir Lamouri <mlamouri@chromium.org>
Reviewed-by: Raymond Toy <rtoy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#535690}
[modify] https://crrev.com/488dc7f72001e12a112c2ebb074bd33a19bbee0b/third_party/WebKit/LayoutTests/http/tests/webaudio/autoplay-crossorigin-expected.txt
[modify] https://crrev.com/488dc7f72001e12a112c2ebb074bd33a19bbee0b/third_party/WebKit/Source/modules/webaudio/BaseAudioContext.cpp