Make a path constant

Add a constant for the new locked uri.

Change-Id: I3bad24ac7ee806442bdd5e38be61005f081edf0d
diff --git a/core/java/android/provider/Telephony.java b/core/java/android/provider/Telephony.java
index 0865b1d..4584382 100644
--- a/core/java/android/provider/Telephony.java
+++ b/core/java/android/provider/Telephony.java
@@ -1539,6 +1539,9 @@
         public static final Uri CONTENT_DRAFT_URI = Uri.parse(
                 "content://mms-sms/draft");
 
+        public static final Uri CONTENT_LOCKED_URI = Uri.parse(
+                "content://mms-sms/locked");
+
         /***
          * Pass in a query parameter called "pattern" which is the text
          * to search for.