Updated mediawiki/extensions/Wikidata
Project: mediawiki/extensions/Wikibase  d1a8fc56894c32d3db1bac526dafde70343459b0

Fix violation of method contract in SpecialSetSiteLink

The method expects a string as second argument. Right now it
can end up being null, which can then cause an exception
further down.

Change-Id: I7d60272c3dda389615f318231196af7479eff6b3