Use fake audio device in peerconnectioninterface_unittest.cc.

Use fake audio device in peerconnectioninterface_unittest.cc.

This test doesn't actually send/receive any audio; it's only testing
the interface layer. But the fact that it was creating/destroying real
audio devices repeatedly caused problems when tests were run in
parallel. So switching to a fake audio device solves this.

BUG=webrtc:7806
Review-Url: https://codereview.webrtc.org/2997383002
Cr-Commit-Position: refs/heads/master@{#19472}
Committed: https://chromium.googlesource.com/external/webrtc/+/d7850b299bed6af1598800b051c9efda155d97b0

[Taylor Brandstetter, 2017-08-23 02:26:18]

deadbeef@webrtc.org changed reviewers:
+ pthatcher@webrtc.org

[Taylor Brandstetter, 2017-08-23 02:26:19]

PTAL

[pthatcher1, 2017-08-23 04:03:17]

lgtm

[henrika_webrtc, 2017-08-23 08:55:43]

lgtm

[Taylor Brandstetter, 2017-08-23 16:52:00]

The CQ bit was checked by deadbeef@webrtc.org

[commit-bot: I haz the power, 2017-08-23 16:52:08]

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, 2017-08-23 17:59:19]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1503507120367290, "parent_rev":
"60e10c794e8d5740e7295a2e0f0bc697eecdaa3b", "commit_rev":
"d7850b299bed6af1598800b051c9efda155d97b0"}

[commit-bot: I haz the power, 2017-08-23 17:59:24]

Description was changed from

==========
Use fake audio device in peerconnectioninterface_unittest.cc.

This test doesn't actually send/receive any audio; it's only testing
the interface layer. But the fact that it was creating/destroying real
audio devices repeatedly caused problems when tests were run in
parallel. So switching to a fake audio device solves this.

BUG=webrtc:7806
==========

to

==========
Use fake audio device in peerconnectioninterface_unittest.cc.

This test doesn't actually send/receive any audio; it's only testing
the interface layer. But the fact that it was creating/destroying real
audio devices repeatedly caused problems when tests were run in
parallel. So switching to a fake audio device solves this.

BUG=webrtc:7806

Review-Url: https://codereview.webrtc.org/2997383002
Cr-Commit-Position: refs/heads/master@{#19472}
Committed:
https://chromium.googlesource.com/external/webrtc/+/d7850b299bed6af1598800b05...
==========

[commit-bot: I haz the power, 2017-08-23 17:59:26]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/external/webrtc/+/d7850b299bed6af1598800b05...