Revert 181105

Compialtion error:

media/audio/linux/alsa_output.cc: In member function 'snd_pcm_sframes_t media::AlsaPcmOutputStream::GetCurrentDelay()':
media/audio/linux/alsa_output.cc:600: error: no matching function for call to 'max(long int, long unsigned int)'
make: *** [out/Debug/obj.target/media/media/audio/linux/alsa_output.o] Error 1

> Reduce Linux low latency buffer size to 512.
> 
> Since ALSA uses an internally large buffer that we fill piecemeal
> by our internal buffer size, we can reduce our internal size in
> exchange for more frequent callbacks.  This change:
> 
> - Removes kernel timeslice adjustment.  Shouldn't be necessary on
> modern kernels.
> - Removes minimum callback time between OnMoreData() calls in favor
> of locking the shared memory (192kHz audio isn't possible otherwise).
> - Fixes jitter introduced by premature clipping of delay information.
> - Removes useless code paths.
> - Switches to using TimeDelta throughout for accuracy.
> - Initializes playback with silence to avoid 192kHz startup glitches.
> 
> This resolves playback issues with 192kHz content and latency issues
> as noted by our performance tests.  With the shared memory block in
> place we should not see any glitching from the new buffer size.
> 
> I believe the benefits of a 512-frame buffer w/ blocking shared mem
> are worth it in comparison to a 2048-frame buffer w/o blocking.
> 
> BUG=172030
> TEST=audio playback is smooth, doesn't glitch, latency tests show ~60ms
> which is inline with Windows/Mac.
> 
> 
> Review URL: https://chromiumcodereview.appspot.com/12051082

TBR=dalecurtis@chromium.org
Review URL: https://codereview.chromium.org/12217052

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@181117 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 0 insertions, 2 deletions

diff --git a/media/audio/audio_util.cc b/media/audio/audio_util.cc
index fe7b7ec..c03f502 100644
--- a/media/audio/audio_util.cc
+++ b/media/audio/audio_util.cc
@@ -200,8 +200,6 @@ size_t GetAudioHardwareBufferSize() {
   HRESULT hr = CoreAudioUtil::GetPreferredAudioParameters(eRender, eConsole,
                                                           &params);
   return FAILED(hr) ? kFallbackBufferSize : params.frames_per_buffer();
-#elif defined(OS_LINUX)
-  return 512;
 #else
   return 2048;
 #endif