Add a TETHER_PRIVILEGED permission and use it where needed.

BUG: 26247383
Change-Id: I73f7227d77926faa9081e83eccb83c8ddee33e08
diff --git a/packages/SystemUI/AndroidManifest.xml b/packages/SystemUI/AndroidManifest.xml
index 9546c8d..66a3336 100644
--- a/packages/SystemUI/AndroidManifest.xml
+++ b/packages/SystemUI/AndroidManifest.xml
@@ -58,6 +58,7 @@
     <uses-permission android:name="android.permission.OVERRIDE_WIFI_CONFIG" />
     <uses-permission android:name="android.permission.MANAGE_NETWORK_POLICY" />
     <uses-permission android:name="android.permission.CONNECTIVITY_INTERNAL" />
+    <uses-permission android:name="android.permission.TETHER_PRIVILEGED" />
     <uses-permission android:name="android.permission.READ_NETWORK_USAGE_HISTORY" />
     <uses-permission android:name="android.permission.CONTROL_VPN" />
     <uses-permission android:name="android.permission.PEERS_MAC_ADDRESS"/>