In general, the router only matches and loads a single Route config tree. However,
named outlets with empty paths are a special case where the router can
and should actually match two different `Route`s and ensure that the
modules are loaded for each match.
This change updates the "ApplyRedirects" stage to ensure that named
outlets with empty paths finish loading their configs before proceeding
to the next stage in the routing pipe. This is necessary because if the
named outlet has `loadChildren` but the associated lazy config is not loaded
before following stages attempt to match and activate relevant `Route`s,
an error will occur.
fixes#12842
PR Close#38379
7ad32649c0