Introduce Settings.Global.WIFI_DEVICE_OWNER_CONFIGS_LOCKDOWN

This setting controls whether WiFi configurations created by a Device Owner app
should be locked down (that is, editable or removable only by the Device Owner).

Bug: 21427528
Change-Id: I0f8fb72bf9da1597e08d3dfc631d37b6b4178ff5
diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 37645b5..7967840 100644
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -6655,6 +6655,17 @@
            "wifi_mobile_data_transition_wakelock_timeout_ms";
 
        /**
+        * This setting controls whether WiFi configurations created by a Device Owner app
+        * should be locked down (that is, be editable or removable only by the Device Owner App,
+        * not even by Settings app).
+        * This setting takes integer values. Non-zero values mean DO created configurations
+        * are locked down. Value of zero means they are not. Default value in the absence of
+        * actual value to this setting is 0.
+        */
+       public static final String WIFI_DEVICE_OWNER_CONFIGS_LOCKDOWN =
+               "wifi_device_owner_configs_lockdown";
+
+       /**
         * The operational wifi frequency band
         * Set to one of {@link WifiManager#WIFI_FREQUENCY_BAND_AUTO},
         * {@link WifiManager#WIFI_FREQUENCY_BAND_5GHZ} or