Reland 7976047 to fix the alsa output scheduling for low latency audio. This patch is to allow using 10ms buffersize or above, and it also optimize the WebAudio performance by using 5ms as the minimum interview between two OnMoreData() calls.
Reland 7976047 to fix the alsa output scheduling for low latency audio.
This patch is to allow using 10ms buffersize or above, and it also optimize the WebAudio performance by using 5ms as the minimum interview between two OnMoreData() calls.

Bug=None
Test=media_unittests, manully tests:
WebAudio: http://chromium.googlecode.com/svn/trunk/samples/audio/shiny-drum-machine.html (change audio_util.cc to return 512 as buffersize)
WebRTC: Internal test app
Html5: http://www.youtube.com/watch?v=siOHh0uzcuY
Chromebook: http://www.youtube.com/watch?v=-9AtssRoc2Q&feature=related

Review URL: http://codereview.chromium.org/8465018

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@109852 0039d316-1c4b-4281-b951-d872f2087c98

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