Remove progress bar for guestfs.launch() progress

In Guestfs you get notifications about progress on some functions like
launch() by registring callback functions. When using guestfs from python,
this is fragile. If the callback functions raises an exception, you end up
with segmentation fault. It is better to completely remove the progress
monitoring from launch().

image_creator/disk.py

@@ -205,15 +205,18 @@ class DiskDevice(object):
 
     def enable(self):
         """Enable a newly created DiskDevice"""
-        self.progressbar = self.out.Progress(100, "Launching helper VM",
-                                             "percent")
-        eh = self.g.set_event_callback(self.progress_callback,
-                                       guestfs.EVENT_PROGRESS)
+
+        self.out.output('Launching helper VM (may take a while) ...', False)
+        # self.progressbar = self.out.Progress(100, "Launching helper VM",
+        #                                     "percent")
+        # eh = self.g.set_event_callback(self.progress_callback,
+        #                               guestfs.EVENT_PROGRESS)
         self.g.launch()
         self.guestfs_enabled = True
-        self.g.delete_event_callback(eh)
-        self.progressbar.success('done')
-        self.progressbar = None
+        # self.g.delete_event_callback(eh)
+        # self.progressbar.success('done')
+        # self.progressbar = None
+        self.out.success('done')
 
         self.out.output('Inspecting Operating System ...', False)
         roots = self.g.inspect_os()
@@ -244,11 +247,11 @@ class DiskDevice(object):
             # Close the guestfs handler if open
             self.g.close()
 
-    def progress_callback(self, ev, eh, buf, array):
-        position = array[2]
-        total = array[3]
-
-        self.progressbar.goto((position * 100) // total)
+#    def progress_callback(self, ev, eh, buf, array):
+#        position = array[2]
+#        total = array[3]
+#
+#        self.progressbar.goto((position * 100) // total)
 
     def mount(self, readonly=False):
         """Mount all disk partitions in a correct order."""