Reland of Use mojo support for Blink devicechange event.

Reland of Use mojo support for Blink devicechange event. (patchset #1 id:1 of https://codereview.chromium.org/2483413002/ )

Reason for revert:
Relanding since the relanding of MediaStreamTrack.getSources (the ermoval of which is interfering with perf tests) will have to be manual anyway.

Original issue's description:
> Revert of Use mojo support for Blink devicechange event. (patchset #3 id:120001 of https://codereview.chromium.org/2476153002/ )
>
> Reason for revert:
> Reverting due to this CL due to it blocking the revert of another CL that is interfering with perf tests. Will reland after that.
>
> See crbug.com/662414
>
> Original issue's description:
> > Use mojo support for Blink devicechange event.
> >
> > BUG=648183
> >
> > Committed: https://crrev.com/6a0339c962198b75c333eb14bafa6374890d738a
> > Cr-Commit-Position: refs/heads/master@{#430318}
>
> TBR=hbos@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=648183
>
> Committed: https://crrev.com/d9a27e0a82856485f39a73863431211475bf8789
> Cr-Commit-Position: refs/heads/master@{#430899}

TBR=hbos@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=648183
Committed: https://crrev.com/662a6038482e0b7bb1d3893491cdcbac33a807f2
Cr-Commit-Position: refs/heads/master@{#430901}

[Guido Urdaneta, 2016-11-09 09:18:54]

The CQ bit was checked by guidou@chromium.org

[Guido Urdaneta, 2016-11-09 09:18:54]

Created Reland of Use mojo support for Blink devicechange event.

[commit-bot: I haz the power, 2016-11-09 09:19:05]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-09 09:20:10]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-11-09 09:22:28]

Description was changed from

==========
Reland of Use mojo support for Blink devicechange event. (patchset #1 id:1 of
https://codereview.chromium.org/2483413002/ )

Reason for revert:
Relanding since the relanding of MediaStreamTrack.getSources (the ermoval of
which is interfering with perf tests) will have to be manual anyway.

Original issue's description:
> Revert of Use mojo support for Blink devicechange event. (patchset #3
id:120001 of https://codereview.chromium.org/2476153002/ )
> 
> Reason for revert:
> Reverting due to this CL due to it blocking the revert of another CL that is
interfering with perf tests. Will reland after that.
> 
> See crbug.com/662414
> 
> Original issue's description:
> > Use mojo support for Blink devicechange event.
> >
> > BUG=648183
> >
> > Committed: https://crrev.com/6a0339c962198b75c333eb14bafa6374890d738a
> > Cr-Commit-Position: refs/heads/master@{#430318}
> 
> TBR=hbos@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=648183
> 
> Committed: https://crrev.com/d9a27e0a82856485f39a73863431211475bf8789
> Cr-Commit-Position: refs/heads/master@{#430899}

TBR=hbos@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=648183
==========

to

==========
Reland of Use mojo support for Blink devicechange event. (patchset #1 id:1 of
https://codereview.chromium.org/2483413002/ )

Reason for revert:
Relanding since the relanding of MediaStreamTrack.getSources (the ermoval of
which is interfering with perf tests) will have to be manual anyway.

Original issue's description:
> Revert of Use mojo support for Blink devicechange event. (patchset #3
id:120001 of https://codereview.chromium.org/2476153002/ )
>
> Reason for revert:
> Reverting due to this CL due to it blocking the revert of another CL that is
interfering with perf tests. Will reland after that.
>
> See crbug.com/662414
>
> Original issue's description:
> > Use mojo support for Blink devicechange event.
> >
> > BUG=648183
> >
> > Committed: https://crrev.com/6a0339c962198b75c333eb14bafa6374890d738a
> > Cr-Commit-Position: refs/heads/master@{#430318}
>
> TBR=hbos@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=648183
>
> Committed: https://crrev.com/d9a27e0a82856485f39a73863431211475bf8789
> Cr-Commit-Position: refs/heads/master@{#430899}

TBR=hbos@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=648183

Committed: https://crrev.com/662a6038482e0b7bb1d3893491cdcbac33a807f2
Cr-Commit-Position: refs/heads/master@{#430901}
==========

[commit-bot: I haz the power, 2016-11-09 09:22:29]

Patchset 1 (id:??) landed as
https://crrev.com/662a6038482e0b7bb1d3893491cdcbac33a807f2
Cr-Commit-Position: refs/heads/master@{#430901}