Add a flag to toggle how much the storage manager should retain.

This flag is used to set how many days of storage the automatic
storage manager will retain when clearing data.

Bug: 28965462
Change-Id: I87afafb7d3252d8c390ea43b7c45fd923f911e4e
diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index d558070..aed4e52 100755
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -6246,6 +6246,21 @@
                 "automatic_storage_manager_enabled";
 
         /**
+         * How many days of information for the automatic storage manager to retain on the device.
+         *
+         * @hide
+         */
+        public static final String AUTOMATIC_STORAGE_MANAGER_DAYS_TO_RETAIN =
+                "automatic_storage_manager_days_to_retain";
+
+        /**
+         * Default number of days of information for the automatic storage manager to retain.
+         *
+         * @hide
+         */
+        public static final int AUTOMATIC_STORAGE_MANAGER_DAYS_TO_RETAIN_DEFAULT = 90;
+
+        /**
          * This are the settings to be backed up.
          *
          * NOTE: Settings are backed up and restored in the order they appear