Cleanup RtpSender hiding RtpHeaderExtensionLength function.

Cleanup RtpSender hiding RtpHeaderExtensionLength function.
This function has no public use,
removed tests calling it: effect of registering extension is better
tested in AllocatePacket and SendPacket tests.

BUG=webrtc:5565
Committed: https://crrev.com/e441bdb74407dcd0235146086f662d98e886a8da
Cr-Commit-Position: refs/heads/master@{#15258}

[danilchap, 2016-11-28 10:05:02]

danilchap@webrtc.org changed reviewers:
+ sprang@webrtc.org

[sprang_webrtc, 2016-11-28 10:21:39]

lgtm
"+1 line, -110 lines" Woo! :)

[danilchap, 2016-11-28 10:22:39]

The CQ bit was checked by danilchap@webrtc.org

[commit-bot: I haz the power, 2016-11-28 10:22:43]

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, 2016-11-28 10:54:58]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1480328559926310, "parent_rev":
"6a73186a389ce4f7b6035d3b939a672855dc54e7", "commit_rev":
"8ba09ad5ce00bc6522001c8425619785a3a1f435"}

[commit-bot: I haz the power, 2016-11-28 10:55:01]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-11-28 10:55:05]

Description was changed from

==========
Cleanup RtpSender hiding RtpHeaderExtensionLength function.
This function has no public use,
removed tests calling it: effect of registering extension is better
tested in AllocatePacket and SendPacket tests.

BUG=webrtc:5565
==========

to

==========
Cleanup RtpSender hiding RtpHeaderExtensionLength function.
This function has no public use,
removed tests calling it: effect of registering extension is better
tested in AllocatePacket and SendPacket tests.

BUG=webrtc:5565

Committed: https://crrev.com/e441bdb74407dcd0235146086f662d98e886a8da
Cr-Commit-Position: refs/heads/master@{#15258}
==========

[commit-bot: I haz the power, 2016-11-28 10:55:05]

Patchset 1 (id:??) landed as
https://crrev.com/e441bdb74407dcd0235146086f662d98e886a8da
Cr-Commit-Position: refs/heads/master@{#15258}