Merge lp://qastaging/~fhd/unity-2d/fix-for-bug-6600100 into lp://qastaging/unity-2d

16 + if (g_mount_can_unmount(mount)) {
17 + g_mount_unmount_with_operation(mount, G_MOUNT_UNMOUNT_NONE, mountOperation, NULL,
18 + (GAsyncReadyCallback) LauncherDevice::onMountUnmounted,
19 + NULL);
20 + } else {
21 + g_object_unref(mount);
22 + }

The GMount object always need to be unref-ed, not only when if fails to unmount. The code should be something like:

if (mount) {
  if (g_mount_can_unmount(mount)) {
    g_mount_unmount_with_operation(mount, G_MOUNT_UNMOUNT_NONE, mountOperation, NULL,
                                   (GAsyncReadyCallback) LauncherDevice::onMountUnmounted,
                                   NULL);
  }
  g_object_unref(mount);
}

82 + g_object_unref(drive);

If, for some weird reason, drive is null, we can get in trouble. I think you need to check if this variable is set before trying to unref it.