Revert of Revert of Chromecast: Play audio streams not supported by CMA via default renderer

Revert of Revert of Chromecast: Play audio streams not supported by CMA via default renderer (patchset #1 id:1 of https://codereview.chromium.org/981473003/)

Reason for revert:
Hmmm... My revert did not fix the test, so I'm undoing it. :/

Original issue's description:
> Revert of Chromecast: Play audio streams not supported by CMA via default renderer (patchset #5 id:70001 of https://codereview.chromium.org/973633002/)
>
> Reason for revert:
> Audio tests started failing consistently in the next build after this was checked in. See:
> https://build.chromium.org/p/chromium.mac/builders/Mac10.9%20Tests/builds/3762
>
> Not sure if this CL is the culprit, but seems the most likely one, so attempting a revert to see if it fixes the problem.
>
> Error:
> [ RUN      ] AudioRecorderTest.BasicRecordAndStop
> ../../components/audio_modem/audio_recorder_unittest.cc:203: Failure
> Value of: IsRecording()
> Actual: false
> Expected: true
> ../../components/audio_modem/audio_recorder_unittest.cc:208: Failure
> Value of: IsRecording()
> Actual: false
> Expected: true
> ../../components/audio_modem/audio_recorder_unittest.cc:213: Failure
> Value of: IsRecording()
> Actual: false
> Expected: true
> [  FAILED  ] AudioRecorderTest.BasicRecordAndStop (1292 ms)
>
> Original issue's description:
> > Chromecast: Play audio streams not supported by CMA via default renderer
> >
> > For Chromecast we want to choose which media renderer to use based on
> > the types of input content streams. We will use CMA media renderer for
> > media types that are supported by our hardware (H264, AAC, etc) and
> > will use the default media renderer for audio streams other than AAC
> > or Vorbis. This will allow us support software decoding of FLAC and
> > Opus via the default Chrome audio path.
> >
> > BUG=457959
> >
> > Committed: https://crrev.com/2e583073b996e66d62f709dd2ffde9e1ef58b276
> > Cr-Commit-Position: refs/heads/master@{#318941}
>
> TBR=gunsch@chromium.org,lcwu@chromium.org,dalecurtis@chromium.org,servolk@chromium.org
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=457959
>
> Committed: https://crrev.com/ee687fd9c6c2bc41642cd8b65de87fe548a3cf75
> Cr-Commit-Position: refs/heads/master@{#319033}

TBR=gunsch@chromium.org,lcwu@chromium.org,dalecurtis@chromium.org,servolk@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=457959
Committed: https://crrev.com/e67565c3e9a6015c9f259483131d4f69e91494a9
Cr-Commit-Position: refs/heads/master@{#319046}

[Finnur, 2015-03-04 09:57:47]

Created Revert of Revert of Chromecast: Play audio streams not supported by CMA
via default renderer

[commit-bot: I haz the power, 2015-03-04 09:58:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/967933003/1

[commit-bot: I haz the power, 2015-03-04 09:59:09]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-03-04 09:59:44]

Patchset 1 (id:??) landed as
https://crrev.com/e67565c3e9a6015c9f259483131d4f69e91494a9
Cr-Commit-Position: refs/heads/master@{#319046}