Revert of Delete unused file mediacommon.h.

Revert of Delete unused file mediacommon.h. (patchset #1 id:1 of https://codereview.webrtc.org/2437703002/ )

Reason for revert:
Turned out this broke a downstream app. Reverting while investigating.

Original issue's description:
> Delete unused file mediacommon.h.
>
> BUG=None
>
> Committed: https://crrev.com/a34e796a1b59a1068c77a3e36d2a24fd37c08afc
> Cr-Commit-Position: refs/heads/master@{#14689}

TBR=magjed@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=None

Committed: https://crrev.com/ca20e7cfed301982986a4da23c819b4e50b5a6e9
Cr-Commit-Position: refs/heads/master@{#14697}

[nisse-webrtc, 2016-10-20 09:52:39]

The CQ bit was checked by nisse@webrtc.org

[nisse-webrtc, 2016-10-20 09:52:39]

Created Revert of Delete unused file mediacommon.h.

[commit-bot: I haz the power, 2016-10-20 09:52:52]

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

[commit-bot: I haz the power, 2016-10-20 09:53:02]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-10-20 09:53:12]

Description was changed from

==========
Revert of Delete unused file mediacommon.h. (patchset #1 id:1 of
https://codereview.webrtc.org/2437703002/ )

Reason for revert:
Turned out this broke a downstream app. Reverting while investigating.

Original issue's description:
> Delete unused file mediacommon.h.
> 
> BUG=None
> 
> Committed: https://crrev.com/a34e796a1b59a1068c77a3e36d2a24fd37c08afc
> Cr-Commit-Position: refs/heads/master@{#14689}

TBR=magjed@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=None
==========

to

==========
Revert of Delete unused file mediacommon.h. (patchset #1 id:1 of
https://codereview.webrtc.org/2437703002/ )

Reason for revert:
Turned out this broke a downstream app. Reverting while investigating.

Original issue's description:
> Delete unused file mediacommon.h.
>
> BUG=None
>
> Committed: https://crrev.com/a34e796a1b59a1068c77a3e36d2a24fd37c08afc
> Cr-Commit-Position: refs/heads/master@{#14689}

TBR=magjed@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=None

Committed: https://crrev.com/ca20e7cfed301982986a4da23c819b4e50b5a6e9
Cr-Commit-Position: refs/heads/master@{#14697}
==========

[commit-bot: I haz the power, 2016-10-20 09:53:12]

Patchset 1 (id:??) landed as
https://crrev.com/ca20e7cfed301982986a4da23c819b4e50b5a6e9
Cr-Commit-Position: refs/heads/master@{#14697}

[nisse-webrtc, 2016-10-21 06:56:59]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.webrtc.org/2426393006/ by nisse@webrtc.org.

The reason for reverting is: #include of mediacommon.h now deleted in the
offending downstream app..