[geary] Fix connecting to servers with invalidly high UIDVALIDITY values.

[Michael Gratton <mjog src gnome org>]

commit 1679618b5b8e127e20e36682df972bfae15dd91a
Author: Michael James Gratton <mike vee net>
Date:   Wed Jan 11 12:27:58 2017 +1100

    Fix connecting to servers with invalidly high UIDVALIDITY values.
    
    Bug 755424.
    
    * src/engine/imap/message/imap-uid-validity.vala (UIDValidity::MAX):
      Allow values larger than permitted by RFC 3501 since at least one
      server has been sending them.

 src/engine/imap/message/imap-uid-validity.vala |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)
---
diff --git a/src/engine/imap/message/imap-uid-validity.vala b/src/engine/imap/message/imap-uid-validity.vala
index 400d84b..2f9ed82 100644
--- a/src/engine/imap/message/imap-uid-validity.vala
+++ b/src/engine/imap/message/imap-uid-validity.vala
@@ -20,9 +20,13 @@ public class Geary.Imap.UIDValidity : Geary.MessageData.Int64MessageData, Geary.
     
     /**
      * Maximum valid value for a {@link UIDValidity}.
+     *
+     * This is currently larger than what the spec allows for, since
+     * at least one mail server was returning values greater than an
+     * unsigned 32-bit integer. See Bug 755424.
      */
-    public const int64 MAX = 0xFFFFFFFF;
-    
+    public const int64 MAX = 0xFFFFFFFFFFFFFFF;
+
     /**
      * Invalid (placeholder) {@link UIDValidity} value.
      */