[gnome-hwtest-simulator] Make srv-gnome-hwtest.image optional

[Owen Taylor <otaylor src gnome org>]

commit d95e9536f1170faf379ba6cd2369b450f567fcdc
Author: Owen W. Taylor <otaylor fishsoup net>
Date:   Thu Sep 25 19:17:50 2014 -0400

    Make srv-gnome-hwtest.image optional
    
    A separate image for /srv/gnome-hwtest was supported to allow directly
    working off a read-only image. Now that updating works well, this is less
    interesting, so support simply having /srv/gnome-hwtest directly in
    the root image.

 src/machine.js |   10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)
---
diff --git a/src/machine.js b/src/machine.js
index 78fc867..82f0d4c 100644
--- a/src/machine.js
+++ b/src/machine.js
@@ -191,9 +191,13 @@ const ControllerMachine = new Lang.Class({
         drives.push({
             file: application.getHomeFile('controller.image').get_path(),
         });
-        drives.push({
-            file: application.getHomeFile('srv-gnome-hwtest.image').get_path(),
-        });
+
+        let srvGnomeImage = application.getHomeFile('srv-gnome-hwtest.image');
+        if (srvGnomeImage.query_exists(null)) {
+            drives.push({
+                file: application.getHomeFile('srv-gnome-hwtest.image').get_path(),
+            });
+        }
 
         let params = { spicePort: 3501,
                        spicePassword: 'redfish',