Require MODIFY_PHONE_STATE for preferred TTY mode am: 266f2436b9

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/services/Telecomm/+/12673305

Change-Id: I2a73bd57d38a489b275ee8017e762afcba94e4ef
diff --git a/src/com/android/server/telecom/TtyManager.java b/src/com/android/server/telecom/TtyManager.java
index 2d04234..dfddb8f 100644
--- a/src/com/android/server/telecom/TtyManager.java
+++ b/src/com/android/server/telecom/TtyManager.java
@@ -49,7 +49,9 @@
 
         IntentFilter intentFilter = new IntentFilter(
                 TelecomManager.ACTION_TTY_PREFERRED_MODE_CHANGED);
-        mContext.registerReceiver(mReceiver, intentFilter);
+        mContext.registerReceiver(mReceiver, intentFilter,
+                android.Manifest.permission.MODIFY_PHONE_STATE,
+                null);
 
         updateCurrentTtyMode();
     }