TYPO3 Core

I have the following scenario:
- there is an extbase extension that uses the pages table as a model source. The model itself features a small subset of the available table fields.
- later - and not related to that extension - the pages table received a new TCA field (without coresponding DB field, that is not needed) with a custom node type.

Each of those points works flawless on its own. The problem is the combination. While extbase tries to build the datamap for the pages model, it encounters the custom node type field and fails with

Uncaught TYPO3 Exception
#1381512761: Invalid value "CUSTOMNODETYPE" for enumeration "TYPO3\CMS\Core\DataHandling\TableColumnType" 

Adding the requested constant to that mentioned file solves the problem, but it can't be the preferred solution to run a patched or rather forked core forever, just due to a custom node type on the pages table and using extbase.

Upon digging in the core I found a prepared code block that limits building datamaps only for properties. The change goes back to Jochen Rau,

commit 855e650998c7ffa0eb977c074dd54dfa3eeb3535
Author: Jochen Rau <j.rau@web.de>
Date:   Sun May 2 09:37:51 2010 +0000

    [~TASK] Extbase (Persistence): Added comment to build process of a DataMap. Removed debug code.

No explanation is given.
Reintroducing this commented out code resolves the problem with the greedy datamap building. My extension is still fully functional.

So my suggestion is: lets bring us back that piece of code.