[gnome-documents] documents: Check whether it is a collection in canPrint

[Debarshi Ray <debarshir src gnome org>]

commit 0ca5158b71455738ceeed1e5faf32ad069dfd321
Author: Debarshi Ray <debarshir gnome org>
Date:   Wed Jun 7 14:16:17 2017 +0200

    documents: Check whether it is a collection in canPrint
    
    https://bugzilla.gnome.org/show_bug.cgi?id=781533

 src/documents.js |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/src/documents.js b/src/documents.js
index 891de48..71aefde 100644
--- a/src/documents.js
+++ b/src/documents.js
@@ -459,6 +459,9 @@ const DocCommon = new Lang.Class({
     },
 
     canPrint: function(docModel) {
+        if (this.collection)
+            return false;
+
         if (!docModel)
             return false;