[balsa] Needed for previous LibBalsaServer commit

[Peter Bloomfield <peterb src gnome org>]

commit 6ea6f6ff92fe882a025d1772cca0c386c73013af
Author: Peter Bloomfield <PeterBloomfield bellsouth net>
Date:   Mon May 22 18:32:32 2017 -0400

    Needed for previous LibBalsaServer commit
    
        * libbalsa/libbalsa.h: typedef the callback for testing whether
          a server can be reached.

 ChangeLog           |    7 +++++++
 libbalsa/libbalsa.h |    5 +++++
 2 files changed, 12 insertions(+), 0 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index c1b3ee3..7a13d5e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 2017-05-22  Peter Bloomfield  <pbloomfield bellsouth net>
 
+       Needed for previous LibBalsaServer commit
+
+       * libbalsa/libbalsa.h: typedef the callback for testing whether
+         a server can be reached.
+
+2017-05-22  Peter Bloomfield  <pbloomfield bellsouth net>
+
        Implement testing reachability of a server
 
        * libbalsa/server.c (libbalsa_server_can_reach_cb),
diff --git a/libbalsa/libbalsa.h b/libbalsa/libbalsa.h
index bff2fbe..73ed79a 100644
--- a/libbalsa/libbalsa.h
+++ b/libbalsa/libbalsa.h
@@ -64,6 +64,11 @@ typedef struct _LibbalsaVfs LibbalsaVfs;
 #include "address-book-osmo.h"
 #endif
 
+/* Callback for testing whether a mailbox or server can be reached: */
+typedef void LibBalsaCanReachCallback(GObject * object,
+                                      gboolean  can_reach,
+                                      gpointer  cb_data);
+
 #include "mailbox.h"
 #include "mailbox_local.h"
 #include "mailbox_remote.h"