Make OS audio buffer size limits visible.

media/audio/cras/audio_manager_cras.cc

 // Copyright 2013 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.
 
 #include "media/audio/cras/audio_manager_cras.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 
@@ skipping 351 matching lines @@
 }
 
 bool AudioManagerCras::IsDefault(const std::string& device_id, bool is_input) {
   AudioDeviceNames device_names;
   GetAudioDeviceNamesImpl(is_input, &device_names);
   DCHECK(!device_names.empty());
   const AudioDeviceName& device_name = device_names.front();
   return device_name.unique_id == device_id;
 }
 
+int AudioManager::GetMinimumAudioBufferSize(int sample_rate) {
+  return GetMinimumOutputBufferSizePerBoard();
+}
+
+int AudioManager::GetMaximumAudioBufferSize(int sample_rate) {
+  return kMaximumOutputBufferSize;
+}
+
 }  // namespace media