When I try to view the API help page, I get the following error:
Fatal error: Cannot access protected property RepoGroup::$reposInitialised in /home/ki/Projects/mediawiki/core/includes/api/ApiQueryFileRepoInfo.php on line 39
This is the case for both my development installation and the labs cluster.
I checked the Git log for includes/filerepo/ForeignAPIRepo.php and found that the visibility of RepoGroup::$reposInitialised had changed in c3bef4243e93 (i.e. Wednesday night).
It looks like this error could be fixed by unconditionally calling $repoGroup->initialiseRepos() in ApiQueryFileRepoInfo::getInitialisedRepoGroup(). However, there are at least two more errors: "$repoGroup->localRepo->getInfo()" in that file, and as already mentioned on Gerrit, "PHP Fatal error: Cannot access protected property LocalRepo::$oldFileFromRowFactory in /www/translatewiki.net/w/includes/filerepo/file/LocalFile.php on line 997".
So this change should be reverted until all existing code that directly accesses the properties is changed to use getter methods.