Breaking: #72385 - Removed deprecated code from DataHandler 

See forge#72385

Description 

Removed deprecated code from DataHandler

The following properties have been removed:

stripslashes_values clear_flexFormData_vDEFbase include_filefunctions

The following methods have been removed:

checkValue_text() checkValue_input() checkValue_check() checkValue_radio() checkValue_group_select() checkValue_flex()

Additionally, the method getLocalTCE() does not accept any parameter anymore.

Impact 

Using one of these methods or properties will throw a fatal error.

Affected Installations 

An extension relying on one of these public properties or methods will fail.

Migration 

These functions are internal and should not be used outside of the core.