Updated mediawiki/extensions
Project: mediawiki/extensions/Wikibase  267d08cc4d57eb24e3eb7a7e0df2c4584ef23c28

Fix getItemIdForLink in SiteLinkLookup to return ItemId objects

PS1: This needs some adjustements in the code. Only the implementations
and tests are updated in the first patch set.

PS2+: In the following patch sets, other classes are updated, too.

Change-Id: I67824712f5a95aa045da4e08cc18a673abc21c35