Exceptions classes are nearly always value objects, and should in most
cases by newable.
Bug: T247862
Change-Id: I4faa8ec6ea8bc44086cfc8075b32d10eea61e9df
* Inject settings and global instances as dependencies to the
ExternalStoreMedium instances. This includes the local wiki
domain, so that wfWikiId() calls are not scattered around.
* Create ExternalStoreAccess service for read/write logic.
* Deprecate the ExternalStore wrapper methods.
* Add some exception cases for bogus store URLs are used instead
of just giving PHP warnings and failing later.
* Make moveToExternal.php require the type/protocol to decide
which ExternalStoreMedium to use instead of assuming "DB".
* Convert logging calls to use LoggerInterface.
Change-Id: I40c3b5534fc8a31116c4c5eb64ee6e4903a6197a
