ItemSelector renders child items eagerly

Can you attach a reproducer?

This bug was fixed in the package ubuntu-system-settings - 0.1+13.10.20130926.4-0ubuntu1

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ubuntu-system-settings (0.1+13.10.20130926.4-0ubuntu1) saucy; urgency=low

  [ Charles Kerr ]
  * As requested, remove the linefeed between a function's return type
    and its name.

  [ Sebastien Bacher ]
  * security: hide non working PIN and app access settings.
  * battery: hide screen idle delay selection, the backend is not
    working.
  * timezone: some tweaks and fixes - hide the selector, we don't have a
    backend for automatic selection - replace the text widget by label
    from the ubuntu uitk, it fixes the issue with the text being too
    small - update the placeholder string according to the new design.
  * datetime: drop empty list item, it's not in the design.
  * hide reset options until we get some backend code working. The
    factory resets require support for the system image side, the other
    options should be doable from our side later on.
  * hide phone settings, we lack phone app support for call
    forwarding,waiting.
  * update the translation template.
  * background: revert use of the new content-hub, it's buggy (see bug
    #1231368). (LP: #1231368)

  [ William Hua ]
  * Switch to ListView as workaround to LP #1227249. (LP: #1227249)

  [ David Planella ]
  * Add a translator comment for the battery charge level (bug 1210341).
    (LP: #1210341)

  [ Alberto Mardegan ]
  * Load testability driver if the -testability option is given. This
    change is needed in order to make the system-settings application
    and its plugins testable with autopilot (or other testability
    plugins).

  [ Ubuntu daily release ]
  * Automatic snapshot from revision 392
 -- Ubuntu daily release <email address hidden> Thu, 26 Sep 2013 21:44:53 +0000

These can be run on the desktop using qmlscene. The ItemSelectorTest takes time linear to the size of the model to load (increasing it to 10000 or higher makes the window unresponsive for quite some time). The ListViewTest is instantaneous, even though the model size is already 1000000000.