When an item of definition has a Date value, definitions app fails and throws the following error:

ERROR info.magnolia.ui.framework.ContextProperty$Impl   : Failed to dispatch context property change: Failed to create instance of [class info.magnolia.ui.contentapp.browser.ListView]
info.magnolia.objectfactory.MgnlInstantiationException: Failed to create instance of [class info.magnolia.ui.contentapp.browser.ListView]

Caused by: java.lang.IllegalStateException: Unsupported property type in map !? Wed Sep 08 16:05:00 CEST 2010(class java.util.Date)

Steps to reproduce:

1. Add a mock Date property by importing the attached sample of a yaml definition under /modules/multisite/config/sites/travel/parameters
2. Open definitions app and navigate to see the imported value
3. The error is thrown.

The error comes from info.magnolia.config.source.raw.DefinitionRawViewMapWrapper.deriveValue(Object, Object) as there is a reduced variety of allowed types within the if-else statements, which don't include Date, so it may happen with other types as well.

This is not happening in 5.7.7 (definitions-app 1.1.4).