The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/77d2f7e71762c45d55d908bdd76ae6a080083ea4

commit 77d2f7e71762c45d55d908bdd76ae6a080083ea4
Author: Becca Hughes <beccahughes@chromium.org>
Date: Thu Aug 30 01:57:17 2018

[Audio Focus] Move AudioFocusType to AudioFocusManager

Move the AudioFocusType source of truth to AudioFocusManager. As
part of the AudioFocusManager s18n work we should move the
AudioFocusType to AFM. This will mean that MediaSession cannot
become out of sync with AFM and means that when we mojoify
AFM we do not need to make an extra mojo call to get the focus
type.

For MediaSessionImpl this renames audio_focus_type to
desired_audio_focus_type and represents the AudioFocusType that
MediaSessionImpl should request.

BUG= 874559 

Change-Id: If20aac1b4a2239ca64a899a1ba75bbb79d57be0e
Reviewed-on: https://chromium-review.googlesource.com/1176360
Reviewed-by: Dan Sanders <sandersd@chromium.org>
Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Commit-Queue: Becca Hughes <beccahughes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#587412}
[modify] https://crrev.com/77d2f7e71762c45d55d908bdd76ae6a080083ea4/content/browser/media/media_internals.cc
[modify] https://crrev.com/77d2f7e71762c45d55d908bdd76ae6a080083ea4/content/browser/media/session/audio_focus_delegate.h
[modify] https://crrev.com/77d2f7e71762c45d55d908bdd76ae6a080083ea4/content/browser/media/session/audio_focus_delegate_android.cc
[modify] https://crrev.com/77d2f7e71762c45d55d908bdd76ae6a080083ea4/content/browser/media/session/audio_focus_delegate_android.h
[modify] https://crrev.com/77d2f7e71762c45d55d908bdd76ae6a080083ea4/content/browser/media/session/audio_focus_delegate_default.cc
[modify] https://crrev.com/77d2f7e71762c45d55d908bdd76ae6a080083ea4/content/browser/media/session/audio_focus_manager.cc
[modify] https://crrev.com/77d2f7e71762c45d55d908bdd76ae6a080083ea4/content/browser/media/session/audio_focus_manager.h
[modify] https://crrev.com/77d2f7e71762c45d55d908bdd76ae6a080083ea4/content/browser/media/session/audio_focus_manager_unittest.cc
[modify] https://crrev.com/77d2f7e71762c45d55d908bdd76ae6a080083ea4/content/browser/media/session/media_session_impl.cc
[modify] https://crrev.com/77d2f7e71762c45d55d908bdd76ae6a080083ea4/content/browser/media/session/media_session_impl.h
[modify] https://crrev.com/77d2f7e71762c45d55d908bdd76ae6a080083ea4/content/browser/media/session/media_session_impl_browsertest.cc
[modify] https://crrev.com/77d2f7e71762c45d55d908bdd76ae6a080083ea4/content/public/android/java/src/org/chromium/content/browser/AudioFocusDelegate.java