Actionbar and selected item state changes on aborting page creation

Steps to reproduce

• Open pages app and click Add Page action
• Enter page name and select a page template (with a corresponding dialog)
• Click next which opens Page Properties dialog
• Click cancel or close dialog window

Expected results

• The Action bar should be in the same state as it was before page creation action was triggered
• The item selection at the bottom should be the same as it was before page creation

Actual results

• The Action bar shows actions relevant for when a page has been selected 
• The selected item shown at the bottom of workbench is the page name used in Create Page dialog

Development notes

This issue arises from ValueContext still holding the Wrapped Page node from PAGES-271 solution for maintaining page state across HTTP requests, so that the Page can be saved when CommitAction is triggered in Page Properties dialog.