Changes to update APN db via Gservices and ConfigUpdater.

- Adding settings that are updated by Gservices.
- Changes to handle UPDATE_APN_DB intent.
- UPDATE_APN_DB intent triggers update of apns-conf.xml and carriers db.

Change-Id: I65a63f3015da1b827b974d17e48bee4c747544ff
diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index a79970c..61c98a1 100644
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -7395,6 +7395,18 @@
                 "sms_short_codes_metadata_url";
 
         /**
+         * URL for apn_db updates
+         * @hide
+         */
+        public static final String APN_DB_UPDATE_CONTENT_URL = "apn_db_content_url";
+
+        /**
+         * URL for apn_db update metadata
+         * @hide
+         */
+        public static final String APN_DB_UPDATE_METADATA_URL = "apn_db_metadata_url";
+
+        /**
          * URL for cert pinlist updates
          * @hide
          */