Set default sampling rate to 44100 and query the native output sampling rate.

media/base/android/java/src/org/chromium/media/AudioManagerAndroid.java

 // 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.
 
 package org.chromium.media;
 
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.media.AudioManager;
 import android.os.Build;
 import android.util.Log;
 
 import org.chromium.base.CalledByNative;
 import org.chromium.base.JNINamespace;
 
 @JNINamespace("media")
 class AudioManagerAndroid {
     private static final String TAG = AudioManagerAndroid.class.getSimpleName();
+    // Most of Google lead devices use 44.1K as the default sampling rate, 44.1K
+    // is also widely used on other android devices.
+    private static final int DEFAULT_SAMPLING_RATE = 44100;
 
     private final AudioManager mAudioManager;
     private final Context mContext;
 
     private BroadcastReceiver mReceiver;
     private boolean mOriginalSpeakerStatus;
 
     @CalledByNative
     public void setMode(int mode) {
         try {
@@ skipping 40 matching lines @@
         mContext.registerReceiver(mReceiver, filter);
     }
 
     @CalledByNative
     public void unregisterHeadsetReceiver() {
         mContext.unregisterReceiver(mReceiver);
         mReceiver = null;
         mAudioManager.setSpeakerphoneOn(mOriginalSpeakerStatus);
     }
 
+    @CalledByNative
+    public int getNativeOutputSampleRate() {
+        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.JELLY_BEAN_MR1) {
+            String sampleRateString = mAudioManager.getProperty(

[qinmin, 2013/05/16 01:31:23]

nit: No need for 2 if statement:

String sampleRateString = null;
if (...)
  sampleRateString = ....;
return sampleRateString == null ? DEFAULT_SAMPLING_RATE :
Integer.parseInt(sampleRateString);

+                    AudioManager.PROPERTY_OUTPUT_SAMPLE_RATE);
+            return (sampleRateString == null ?
+                    DEFAULT_SAMPLING_RATE : Integer.parseInt(sampleRateString));
+        } else {
+            return DEFAULT_SAMPLING_RATE;
+        }
+    }
+
     private void logDeviceInfo() {
         Log.i(TAG, "Manufacturer:" + Build.MANUFACTURER +
                   " Board: " + Build.BOARD + " Device: " + Build.DEVICE +
                   " Model: " + Build.MODEL + " PRODUCT: " + Build.PRODUCT);
     }
 }