Adding SystemApi for remaining AudioManager errors

Bug: 206121418
Test: Compile apex
Change-Id: Ia0bbabc26132893923706917ce716a6f7375bfe1
diff --git a/core/api/system-current.txt b/core/api/system-current.txt
index d6e4815..11914ff 100644
--- a/core/api/system-current.txt
+++ b/core/api/system-current.txt
@@ -5884,6 +5884,7 @@
     field public static final int DEVICE_VOLUME_BEHAVIOR_VARIABLE = 0; // 0x0
     field public static final String EXTRA_VOLUME_STREAM_TYPE = "android.media.EXTRA_VOLUME_STREAM_TYPE";
     field public static final String EXTRA_VOLUME_STREAM_VALUE = "android.media.EXTRA_VOLUME_STREAM_VALUE";
+    field public static final int FLAG_BLUETOOTH_ABS_VOLUME = 64; // 0x40
     field @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public static final int STREAM_ASSISTANT = 11; // 0xb
     field public static final int STREAM_BLUETOOTH_SCO = 6; // 0x6
     field public static final int SUCCESS = 0; // 0x0
diff --git a/media/java/android/media/AudioManager.java b/media/java/android/media/AudioManager.java
index 1b4c0bc..15a398d 100644
--- a/media/java/android/media/AudioManager.java
+++ b/media/java/android/media/AudioManager.java
@@ -562,6 +562,7 @@
      * Indicates the volume set/adjust call is for Bluetooth absolute volume
      * @hide
      */
+    @SystemApi
     public static final int FLAG_BLUETOOTH_ABS_VOLUME = 1 << 6;
 
     /**