Revert r95841 due to failing media_unittests on linux_shared bot.

media/audio/simple_sources.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_AUDIO_SIMPLE_SOURCES_H_
 #define MEDIA_AUDIO_SIMPLE_SOURCES_H_
 
 #include <list>
 
 #include "media/audio/audio_io.h"
 #include "media/base/seekable_buffer.h"
 
 // An audio source that produces a pure sinusoidal tone.
-class MEDIA_EXPORT SineWaveAudioSource
-    : public AudioOutputStream::AudioSourceCallback {
+class SineWaveAudioSource : public AudioOutputStream::AudioSourceCallback {
  public:
   enum Format {
     FORMAT_8BIT_LINEAR_PCM,
     FORMAT_16BIT_LINEAR_PCM,
   };
   // |channels| is the number of audio channels, |freq| is the frequency in
   // hertz and it has to be less than half of the sampling frequency
   // |sample_freq| or else you will get aliasing.
   SineWaveAudioSource(Format format, int channels,
                       double freq, double sample_freq);
   virtual ~SineWaveAudioSource() {}
 
   // Implementation of AudioSourceCallback.
   virtual uint32 OnMoreData(
       AudioOutputStream* stream, uint8* dest, uint32 max_size,
       AudioBuffersState audio_buffers);
   virtual void OnError(AudioOutputStream* stream, int code);
 
  protected:
   Format format_;
   int channels_;
   double freq_;
   double sample_freq_;
 };
 
 // Defines an interface for pushing audio output. In contrast, the interfaces
 // defined by AudioSourceCallback are pull model only.
-class MEDIA_EXPORT PushAudioOutput {
+class PushAudioOutput {
  public:
   virtual ~PushAudioOutput() {}
 
   // Write audio data to the audio device. It will be played eventually.
   // Returns false on failure.
   virtual bool Write(const void* data, uint32 len) = 0;
 
   // Returns the number of bytes that have been buffered but not yet given
   // to the audio device.
   virtual uint32 UnProcessedBytes() = 0;
 };
 
 // A fairly basic class to connect a push model provider PushAudioOutput to
 // a pull model provider AudioSourceCallback. Fundamentally it manages a series
 // of audio buffers and is unaware of the actual audio format.
 // Note that the PushSource is not thread safe and user need to provide locking.
-class MEDIA_EXPORT PushSource
+class PushSource
     : public AudioOutputStream::AudioSourceCallback,
       public PushAudioOutput {
  public:
   PushSource();
   virtual ~PushSource();
 
   // Write one buffer.
   virtual bool Write(const void* data, uint32 len);
 
   // Return the total number of bytes not given to the audio device yet.
   virtual uint32 UnProcessedBytes();
 
   // Implementation of AudioSourceCallback.
   virtual uint32 OnMoreData(AudioOutputStream* stream, uint8* dest,
                             uint32 max_size, AudioBuffersState buffers_state);
   virtual void OnError(AudioOutputStream* stream, int code);
 
   // Discard all buffered data and reset to initial state.
   void ClearAll();
 
  private:
   // Free acquired resources.
   void CleanUp();
 
   media::SeekableBuffer buffer_;
 };
 
 #endif  // MEDIA_AUDIO_SIMPLE_SOURCES_H_