Always-on VPN.

Adds support for always-on VPN profiles. Users pick an always-on VPN
from list of existing VPN profiles, which must use an IP address for
both VPN server and DNS.  Moved "add" operation into action bar.

Bug: 5756357
Change-Id: I4c7ed7f2a3b027be1baf65c08213336a61f3acfe

res/layout/vpn_lockdown_editor.xml

@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2012 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:orientation="vertical"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content">
+
+    <TextView
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:paddingLeft="16dip"
+        android:paddingRight="16dip"
+        android:paddingTop="8dip"
+        android:paddingBottom="8dip"
+        android:textAppearance="?android:attr/textAppearanceMedium"
+        android:text="@string/vpn_lockdown_summary" />
+
+    <ListView
+        android:id="@android:id/list"
+        android:layout_width="match_parent"
+        android:layout_height="0dip"
+        android:layout_weight="1" />
+
+</LinearLayout>