PageHeadState doens't correctly update head.contents

This seems similar to bug 1341814 where the head contents are not correctly handled when switching page head state.

Yes they are definitely similar. Feel free to mark this bug as duplicate if you want.
Thanks nik :)

If you're developing targeting ubuntu-sdk-14.10 as toolkit, you could use the workaround in the page definition:

        property Item __oldContents: null
        Connections {
            target: page.head
            onContentsChanged: {
                if (page.__oldContents) {
                    page.__oldContents.parent = null;
                }
                page.__oldContents = page.head.contents;
            }
        }

see also the attached file.

This bug was fixed in the package ubuntu-ui-toolkit - 1.1.1376+15.04.20150111-0ubuntu1

---------------
ubuntu-ui-toolkit (1.1.1376+15.04.20150111-0ubuntu1) vivid; urgency=medium

  [ Tim Peeters ]
  * Add a preview of the new list items to the UITK component gallery.

  [ Zoltan Balogh ]
  * Update the test plan and fix the PPA string in case it contains backslash.
  * Added Dialog CPO to test if OSK pushes up the the dialog.

  [ Zsombor Egri ]
  * ListItem highlight is driven also by the connection of a slot to
    the clicked() signal. This will also be applied when pressAndHold
    signal will be introduced. Fixes LP: #1399025

  [ Giulio Collura ]
  * Force the removal of the previous 'contents' item by removing its parent.
    This way we ensure that the contents are correctly hidden, focused and
    removed, without destroying them. Fixes LP: #1341814 LP: #1400297
 -- Ubuntu daily release <email address hidden> Sun, 11 Jan 2015 18:57:02 +0000

Please backport this to RTM as well. :)