Revert of Revert "Remove MediaStreamTrack.getSources()."

Revert of Revert "Remove MediaStreamTrack.getSources()." (patchset #2 id:20001 of https://codereview.chromium.org/2489823002/ )

Reason for revert:
Relanding since the performance test affected by this revert is being fixed.

Original issue's description:
> Revert "Remove MediaStreamTrack.getSources()."
>
> This reverts commit 3ea42b21339ebf028e0ff6e368ca60d463386dd2.
>
> This revert is temporary in order to give time to a performance test to
> be fixed.
>
> TBR=rbyers@chromium.org, hbos@chromium.org
> BUG=662414, 649710, 388194
>
> Committed: https://crrev.com/f29875a0a4fb3ddfa70620fbee5cb7c33f15a78d
> Cr-Commit-Position: refs/heads/master@{#431224}

TBR=
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=662414, 649710, 388194
Committed: https://crrev.com/d4fd7e55ab9824704b0b60bd9ac624e184b0904f
Cr-Commit-Position: refs/heads/master@{#431289}

[Guido Urdaneta, 2016-11-10 18:05:51]

The CQ bit was checked by guidou@chromium.org

[Guido Urdaneta, 2016-11-10 18:05:52]

Created Revert of Revert "Remove MediaStreamTrack.getSources()."

[commit-bot: I haz the power, 2016-11-10 18:06:37]

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, 2016-11-10 18:08:11]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-11-10 18:38:34]

Description was changed from

==========
Revert of Revert "Remove MediaStreamTrack.getSources()." (patchset #2 id:20001
of https://codereview.chromium.org/2489823002/ )

Reason for revert:
Relanding since the performance test affected by this revert is being fixed.

Original issue's description:
> Revert "Remove MediaStreamTrack.getSources()."
> 
> This reverts commit 3ea42b21339ebf028e0ff6e368ca60d463386dd2.
> 
> This revert is temporary in order to give time to a performance test to
> be fixed.
> 
> TBR=rbyers@chromium.org, hbos@chromium.org
> BUG=662414, 649710, 388194
> 
> Committed: https://crrev.com/f29875a0a4fb3ddfa70620fbee5cb7c33f15a78d
> Cr-Commit-Position: refs/heads/master@{#431224}

TBR=
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=662414, 649710, 388194
==========

to

==========
Revert of Revert "Remove MediaStreamTrack.getSources()." (patchset #2 id:20001
of https://codereview.chromium.org/2489823002/ )

Reason for revert:
Relanding since the performance test affected by this revert is being fixed.

Original issue's description:
> Revert "Remove MediaStreamTrack.getSources()."
>
> This reverts commit 3ea42b21339ebf028e0ff6e368ca60d463386dd2.
>
> This revert is temporary in order to give time to a performance test to
> be fixed.
>
> TBR=rbyers@chromium.org, hbos@chromium.org
> BUG=662414, 649710, 388194
>
> Committed: https://crrev.com/f29875a0a4fb3ddfa70620fbee5cb7c33f15a78d
> Cr-Commit-Position: refs/heads/master@{#431224}

TBR=
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=662414, 649710, 388194

Committed: https://crrev.com/d4fd7e55ab9824704b0b60bd9ac624e184b0904f
Cr-Commit-Position: refs/heads/master@{#431289}
==========

[commit-bot: I haz the power, 2016-11-10 18:38:36]

Patchset 1 (id:??) landed as
https://crrev.com/d4fd7e55ab9824704b0b60bd9ac624e184b0904f
Cr-Commit-Position: refs/heads/master@{#431289}