[evolution-data-server] Add a comment explaining CamelStore's mode field.

[Matthew Barnes <mbarnes src gnome org>]

commit 9c9c2fb4c5aba412c8e2e44afd7541b82c8a5695
Author: Matthew Barnes <mbarnes redhat com>
Date:   Sat Oct 29 11:16:03 2011 -0400

    Add a comment explaining CamelStore's mode field.
    
    I was about to get rid of this field thinking it was unused, but as
    usual it's a GroupWise-specific hack for non-writable proxy accounts.
    Add a comment to the header file for future reference.

 camel/camel-store.h |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/camel/camel-store.h b/camel/camel-store.h
index 6ef1749..76a93fc 100644
--- a/camel/camel-store.h
+++ b/camel/camel-store.h
@@ -128,6 +128,11 @@ struct _CamelStore {
 	struct _CamelDB *cdb_w;
 
 	CamelStoreFlags flags;
+
+	/* XXX The default "mode" (read/write) is changed only by
+	 *     evolution-groupwise for non-writable proxy accounts.
+	 *     The mode is only checked by the account combo box in
+	 *     Evolution's composer window. */
 	CamelStorePermissionFlags mode;
 
 	/* Future ABI expansion */