Add Environment call: get config dir for some user

This returns a read-only directory accessible to any app running as the
same user, containing various configuration files written by the system.

Change-Id: I635de184fc285b8fef166b782bbc1ac79f8f0687
diff --git a/core/java/android/os/Environment.java b/core/java/android/os/Environment.java
index 7bf7367..b554e9f 100644
--- a/core/java/android/os/Environment.java
+++ b/core/java/android/os/Environment.java
@@ -319,6 +319,17 @@
     }
 
     /**
+     * Returns the config directory for a user. This is for use by system services to store files
+     * relating to the user which should be readable by any app running as that user.
+     *
+     * @hide
+     */
+    public static File getUserConfigDirectory(int userId) {
+        return new File(new File(new File(
+                getDataDirectory(), "misc"), "user"), Integer.toString(userId));
+    }
+
+    /**
      * Returns whether the Encrypted File System feature is enabled on the device or not.
      * @return <code>true</code> if Encrypted File System feature is enabled, <code>false</code>
      * if disabled.