Point users of AudioManager.setBluetoothA2dpOn to MediaRouter

Bug: 238081912
Test: N/A. Javadoc change.
Change-Id: Iadd0713ee216cddb03dbd5d4e4cc7d1116932148
diff --git a/media/java/android/media/AudioManager.java b/media/java/android/media/AudioManager.java
index 6922637..2547a963 100644
--- a/media/java/android/media/AudioManager.java
+++ b/media/java/android/media/AudioManager.java
@@ -2812,9 +2812,7 @@
     }
 
     /**
-     * @param on set <var>true</var> to route A2DP audio to/from Bluetooth
-     *           headset; <var>false</var> disable A2DP audio
-     * @deprecated Do not use.
+     * @deprecated Use {@link MediaRouter#selectRoute} instead.
      */
     @Deprecated public void setBluetoothA2dpOn(boolean on){
     }