Merge pull request #12778 from owncloud/searchbytags2

apps/files_sharing/lib/cache.php

apps/files_sharing/tests/cache.php

lib/private/files/cache/cache.php

lib/private/files/cache/wrapper/cachejail.php

lib/private/files/cache/wrapper/cachewrapper.php

lib/private/files/filesystem.php

lib/private/files/node/folder.php

lib/private/files/node/nonexistingfolder.php

lib/private/files/view.php

lib/private/server.php

lib/private/tagmanager.php

lib/public/files/folder.php

lib/public/itagmanager.php

tests/lib/files/cache/cache.php

tests/lib/files/node/folder.php

tests/lib/tags.php

tests/lib/testcase.php