Updated documentation

Change-Id: Idfb667430ffdd412adb5b490953427a0c58fd448
diff --git a/src/com/android/mail/providers/UIProvider.java b/src/com/android/mail/providers/UIProvider.java
index 5689227..57c4b72 100644
--- a/src/com/android/mail/providers/UIProvider.java
+++ b/src/com/android/mail/providers/UIProvider.java
@@ -237,6 +237,8 @@
          * results.
          * The supported query parameters are limited to those listed
          * in {@link #SearchQueryParameters}
+         * The cursor returned from this query is expected have one row, where the columnm are a
+         * subset of the columns specified in {@link #FolderColumns}
          */
         public static final String SEARCH_URI = "searchUri";