Reland of Adding the ability to change ICE servers through SetConfiguration.

Reland of Adding the ability to change ICE servers through SetConfiguration. (patchset #1 id:1 of https://codereview.webrtc.org/1424803004/ )

Reason for revert:
Relanding with compile warning fixed.

Original issue's description:
> Revert of Adding the ability to change ICE servers through SetConfiguration. (patchset #7 id:120001 of https://codereview.webrtc.org/1391013007/ )
>
> Reason for revert:
> Caused compiler warning, breaking Chrome FYI bots.
>
> Original issue's description:
> > Adding the ability to change ICE servers through SetConfiguration.
> >
> > Added a SetIceServers method to PortAllocator. Also added a new
> > PeerConnection Initialize method that takes a PortAllocator, in the
> > hope that we can get rid of PortAllocatorFactoryInterface, since the
> > only substantial thing a factory does is convert the webrtc:: ICE
> > servers to cricket:: versions.
> >
> > Committed: https://crrev.com/d3b26d94399ff539db375a9b84010ee75479d4cf
> > Cr-Commit-Position: refs/heads/master@{#10420}
>
> TBR=pthatcher@webrtc.org
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
>
> Committed: https://crrev.com/18a944bf0ac9eed872dc009bd58e6bc12c946303
> Cr-Commit-Position: refs/heads/master@{#10421}

TBR=pthatcher@webrtc.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Committed: https://crrev.com/653b8e02f22c9b6ba38be1cf4c0fa101894a9407
Cr-Commit-Position: refs/heads/master@{#10609}

[Taylor Brandstetter, 2015-10-27 02:38:47]

Created Reland of Adding the ability to change ICE servers through
SetConfiguration.

[Taylor Brandstetter, 2015-11-11 00:19:17]

bump

[pthatcher1, 2015-11-11 00:45:39]

lgtm

[Taylor Brandstetter, 2015-11-11 20:54:48]

The CQ bit was checked by deadbeef@webrtc.org

[commit-bot: I haz the power, 2015-11-11 20:54:58]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1414313003/230001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1414313003/230001

[commit-bot: I haz the power, 2015-11-11 20:55:16]

Committed patchset #2 (id:230001)

[commit-bot: I haz the power, 2015-11-11 20:55:28]

Patchset 2 (id:??) landed as
https://crrev.com/653b8e02f22c9b6ba38be1cf4c0fa101894a9407
Cr-Commit-Position: refs/heads/master@{#10609}

[tommi, 2015-11-13 17:01:57]

On 2015/11/11 20:55:28, commit-bot: I haz the power wrote:
> Patchset 2 (id:??) landed as
> https://crrev.com/653b8e02f22c9b6ba38be1cf4c0fa101894a9407
> Cr-Commit-Position: refs/heads/master@{#10609}

Out of curiosity, why bypassing all the checks?

TBR=pthatcher@webrtc.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

[tommi, 2015-11-13 17:16:01]

On 2015/11/13 at 17:01:57, tommi (webrtc) wrote:
> On 2015/11/11 20:55:28, commit-bot: I haz the power wrote:
> > Patchset 2 (id:??) landed as
> > https://crrev.com/653b8e02f22c9b6ba38be1cf4c0fa101894a9407
> > Cr-Commit-Position: refs/heads/master@{#10609}
> 
> Out of curiosity, why bypassing all the checks?
> 
> TBR=pthatcher@webrtc.org
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true

nevermind, the multiple reverts confused me.