add permission for AudioManager routing APIs.

Add signature or system permission
"android.permission.MODIFY_AUDIO_ROUTING" for AudioManager APIs
allowing system services and applications to modify audio routing.

Bug: 14815883.
Change-Id: If09f6f3a166a6b2f3761b65dbde0c86873850f07
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index 55f52da..9e378da 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -2225,6 +2225,14 @@
         android:description="@string/permdesc_captureAudioHotword"
         android:protectionLevel="signature|system" />
 
+    <!-- Allows an application to modify audio routing and override policy decisions.
+         <p>Not for use by third-party applications.</p>
+         @hide -->
+    <permission android:name="android.permission.MODIFY_AUDIO_ROUTING"
+        android:label="@string/permlab_modifyAudioRouting"
+        android:description="@string/permdesc_modifyAudioRouting"
+        android:protectionLevel="signature|system" />
+
     <!-- Allows an application to capture video output.
          <p>Not for use by third-party applications.</p> -->
     <permission android:name="android.permission.CAPTURE_VIDEO_OUTPUT"