[geary/wip/765516-gtk-widget-conversation-viewer: 177/207] Fix a possible crit error when cancelling conversation load.

[Michael Gratton <mjog src gnome org>]

commit 5de63c60f5a06f89cb488a2c064630ffaf9d8f1b
Author: Michael James Gratton <mike vee net>
Date:   Mon Sep 12 15:05:32 2016 +1000

    Fix a possible crit error when cancelling conversation load.

 .../conversation-viewer/conversation-email.vala    |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/src/client/conversation-viewer/conversation-email.vala 
b/src/client/conversation-viewer/conversation-email.vala
index 35ccab0..12e2f05 100644
--- a/src/client/conversation-viewer/conversation-email.vala
+++ b/src/client/conversation-viewer/conversation-email.vala
@@ -675,6 +675,9 @@ public class ConversationEmail : Gtk.Box {
             }
 
             foreach (Geary.Attachment attachment in this.displayed_attachments) {
+                if (load_cancelled.is_cancelled()) {
+                    return;
+                }
                 AttachmentView view = new AttachmentView(attachment);
                 this.attachments_view.add(view);
                 yield view.load_icon(load_cancelled);