Fix chromeos=1 so Pulse is preferred when use_cras=0.

media/audio/cras/audio_manager_cras.h

Index: media/audio/cras/audio_manager_cras.h
diff --git a/media/audio/cras/audio_manager_cras.h b/media/audio/cras/audio_manager_cras.h
index 589374ae0b9ae047a415a10dcc4ccf97657d97e0..b2863a6d602a970e3b4c6f9265a9d42b81ba3c16 100644
--- a/media/audio/cras/audio_manager_cras.h
+++ b/media/audio/cras/audio_manager_cras.h
@@ -5,6 +5,8 @@
 #ifndef MEDIA_AUDIO_CRAS_AUDIO_MANAGER_CRAS_H_
 #define MEDIA_AUDIO_CRAS_AUDIO_MANAGER_CRAS_H_
 
+#include <cras_types.h>
+
 #include <string>
 
 #include "base/compiler_specific.h"
@@ -40,6 +42,8 @@ class MEDIA_EXPORT AudioManagerCras : public AudioManagerBase {
   virtual AudioInputStream* MakeLowLatencyInputStream(
       const AudioParameters& params, const std::string& device_id) OVERRIDE;
 
+  static snd_pcm_format_t BitsToFormat(int bits_per_sample);
+
  protected:
   virtual ~AudioManagerCras();