Add #can_unsubscribe? to SentNotification

app/models/sent_notification.rb

@@ -62,6 +62,10 @@ class SentNotification < ActiveRecord::Base
     end
   end
 
+  def can_unsubscribe?
+    !for_commit?
+  end
+
   def for_commit?
     noteable_type == "Commit"
   end

app/views/layouts/notify.html.haml

@@ -45,7 +45,7 @@
           -# Don't link the host is the line below, one link in the email is easier to quickly click than two.
           You're receiving this email because of your account on #{Gitlab.config.gitlab.host}.
           If you'd like to receive fewer emails, you can
-          - if @sent_notification && !@sent_notification.for_commit?
+          - if @sent_notification && @sent_notification.can_unsubscribe?
             = link_to "unsubscribe", unsubscribe_sent_notification_url(@sent_notification)
             from this thread or
           adjust your notification settings.