Revert 269354 "Added automatic mode to FakeInputAudioStream to g..."

This CL caused the MediaAccessAPIDeny_TestDenyWithPreventDefault to fail on the mac builders.
The same test also failed in the mac chromium rel browser tests try runs. Sadly they showed up
as green.

Please fix and reland

> Added automatic mode to FakeInputAudioStream to generate automatic beeps.
> 
> This patch is to allow writing audio only tests using the fake input stream, also it changes the name of the fake device from "Default" to "Fake Audio, which I hope it will make things less confusing.
> 
> TBR=dalecurtis@chromium.org
> NOTRY=true
> 
> BUG=358541
> TEST=bots existing webrtc tests.
> 
> Review URL: https://codereview.chromium.org/272723006

TBR=xians@chromium.org

Review URL: https://codereview.chromium.org/273163002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@269391 0039d316-1c4b-4281-b951-d872f2087c98

• content/browser/renderer_host/media/audio_input_device_manager.cc[diff]
• content/browser/renderer_host/media/audio_input_device_manager.h[diff]
• content/browser/renderer_host/media/audio_input_device_manager_unittest.cc[diff]
• content/browser/renderer_host/media/media_stream_dispatcher_host_unittest.cc[diff]
• media/audio/fake_audio_input_stream.cc[diff]
• media/audio/fake_audio_input_stream.h[diff]
• media/audio/mock_audio_manager.cc[diff]