[geary] Ensure mixed landscape/portrait attachment previews are centred vertically.

[Michael Gratton <mjog src gnome org>]

commit b19d0c8cadc938738a8a41ca66b2f250eaf5b0e3
Author: Michael James Gratton <mike vee net>
Date:   Sat Feb 11 11:39:34 2017 +1100

    Ensure mixed landscape/portrait attachment previews are centred vertically.

 ui/conversation-email-attachment-view.ui |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/ui/conversation-email-attachment-view.ui b/ui/conversation-email-attachment-view.ui
index c23947a..16b5f30 100644
--- a/ui/conversation-email-attachment-view.ui
+++ b/ui/conversation-email-attachment-view.ui
@@ -10,6 +10,8 @@
       <object class="GtkImage" id="icon">
         <property name="visible">True</property>
         <property name="can_focus">False</property>
+        <property name="valign">center</property>
+        <property name="vexpand">True</property>
         <property name="pixel_size">32</property>
         <property name="icon_name">x-office-document</property>
       </object>