Batchload all data required to fix Special:EditWatchlist titles

This will batchload all the data needed for fetch the topic titles'
text when changing how Flow topics are linked to in
Special:EditWatchlist. All data being requested in that particular
hook will already be in memory because we've already fetched it here.

This depends on a core change: I30b3bbb2c5ef131f069a5aabfad8b88bc2cf09df
While this won't break when the core change isn't yet merged, we should
probably just hold off until it is.

Change-Id: Iec21012d15db53e23013aa6c36fed0e24e0ce6fe
Merge "Batchload all data required to fix Special:EditWatchlist titles"