Make OS audio buffer size limits visible.

media/audio/pulse/audio_manager_pulse.cc

Index: media/audio/pulse/audio_manager_pulse.cc
diff --git a/media/audio/pulse/audio_manager_pulse.cc b/media/audio/pulse/audio_manager_pulse.cc
index 6fa330f0e82708556ff7f6d93f31d610c9261da9..e1ea89ad413e5c479161e9d6cf1b5be9126746d5 100644
--- a/media/audio/pulse/audio_manager_pulse.cc
+++ b/media/audio/pulse/audio_manager_pulse.cc
@@ -18,6 +18,7 @@
 #include "media/audio/pulse/pulse_util.h"
 #include "media/base/audio_parameters.h"
 #include "media/base/channel_layout.h"
+#include "media/base/limits.h"
 
 namespace media {
 
@@ -27,10 +28,6 @@ using pulse::WaitForOperationCompletion;
 // Maximum number of output streams that can be open simultaneously.
 static const int kMaxOutputStreams = 50;
 
-// Define bounds for the output buffer size.
-static const int kMinimumOutputBufferSize = 512;
-static const int kMaximumOutputBufferSize = 8192;
-
 // Default input buffer size.
 static const int kDefaultInputBufferSize = 1024;
 
@@ -164,7 +161,7 @@ AudioParameters AudioManagerPulse::GetPreferredOutputStreamParameters(
   // TODO(tommi): Support |output_device_id|.
   VLOG_IF(0, !output_device_id.empty()) << "Not implemented!";
 
-  int buffer_size = kMinimumOutputBufferSize;
+  int buffer_size = limits::kMinAudioBufferSize;
   int bits_per_sample = 16;
 
   // Query native parameters where applicable; Pulse does not require these to
@@ -177,7 +174,7 @@ AudioParameters AudioManagerPulse::GetPreferredOutputStreamParameters(
     bits_per_sample = input_params.bits_per_sample();
     channel_layout = input_params.channel_layout();
     buffer_size =
-        std::min(kMaximumOutputBufferSize,
+        std::min(static_cast<int>(limits::kMaxAudioBufferSize),
                  std::max(buffer_size, input_params.frames_per_buffer()));
   }