Updated mediawiki/extensions
Project: mediawiki/extensions/Wikibase  d88d3de2fb86d9a6f65f3f4ad1e69a033ad9a6cd

Cleanup Entity Serializer code

Rename an $Uppercase variable.

Remove some unused protected variables, just use the one from the
parent object.

Change-Id: I90b643b1812f759e4066310ad7c4669162d1bb4a