I suggest this as the first, most minimal step. This allows us to
slowly remove all the code that uses this flag without breaking
anything on wikis where the feature flag is not enabled. In other
words: this patch turns all code that expects this flag to be false
into dead code. We can then slowly remove said dead code.
Bug: T289049
Change-Id: I523978f7ca72dfc1cc7b64741e2f4f20ed3adfb7
Extensions using Phan need to be updated simultaneously with core due
to T308443.
Bug: T308718
Depends-On: Id08a220e1d6085e2b33f3f6c9d0e3935a4204659
Change-Id: I9a20c25b9cea26e1fbe0f0434a0800632e9e0fc7