[folks] Added the READ_ONLY PersonaStore error

[Travis Reitter <treitter src gnome org>]

commit 236ea55666acbb8c0b21af935d95155c9f25c140
Author: Raul Gutierrez Segales <raul gutierrez segales collabora co uk>
Date:   Mon Jan 10 19:30:33 2011 +0000

    Added the READ_ONLY PersonaStore error

 folks/persona-store.vala |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/folks/persona-store.vala b/folks/persona-store.vala
index 7118cb4..71b7e3d 100644
--- a/folks/persona-store.vala
+++ b/folks/persona-store.vala
@@ -91,6 +91,13 @@ public errordomain Folks.PersonaStoreError
    * @since 0.3.0
    */
   STORE_OFFLINE,
+
+  /**
+   * The { link PersonaStore} doesn't support write operations.
+   *
+   * @since 0.3.4
+   */
+  READ_ONLY,
 }
 
 /**