uIDefaultValueForSetChangedOnPublish does not work

Description

The setting uIDefaultValueForSetChangedOnPublish="true" does not make the property "Update modified date" checked when editing a page.

Steps to Reproduce:
1. In your config file, go to the <applicationSettings>.
2. Set the value uIDefaultValueForSetChangedOnPublish="true".
3. Create a page, go to the Settings tab. See that "Update modified date" is checked.
4. Uncheck the property "Update modified date". Edit some text in your page and publish.
5. Edit the page again.
6. Go to the "Settings" tab. The property Update modified date SHOULD NOW be checked but is not.

Expected: The property Update modified date should be checked.

Actual: The "Update modified date" checkbox does not keep its checked value between edits.