Add permission for dynamic AudioEffect attachment

Add signature or system permission
"android.permission.MODIFY_DEFAULT_AUDIO_EFFECTS" for AudioEffect APIs
allowing system services and applications to modify what effects get
automatically attached to streams/sources/devices of various types.

This permission is hidden for now, since this API is not yet approved
for mainline Android.

Bug: 67964202, 70300942
Test: None
Change-Id: I51b4e3a939e16221633448f646e5129e1a62dd23
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index 472df1a..0bbef40 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -3248,6 +3248,13 @@
     <permission android:name="android.permission.MODIFY_AUDIO_ROUTING"
         android:protectionLevel="signature|privileged" />
 
+    <!-- Allows an application to modify what effects are applied to all audio
+         (matching certain criteria) from any application.
+         <p>Not for use by third-party applications.</p>
+         @hide -->
+    <permission android:name="android.permission.MODIFY_DEFAULT_AUDIO_EFFECTS"
+        android:protectionLevel="signature|privileged" />
+
     <!-- @SystemApi Allows an application to capture video output.
          <p>Not for use by third-party applications.</p> -->
     <permission android:name="android.permission.CAPTURE_VIDEO_OUTPUT"