Right now the logic exists in a few places, both in and outside the
linker. We recently began to use part of the linker pipeline in normal /
all builds so it's easier to share (and unify) the code now.
The real gain is to avoid copying assemblies, in particular large ones,
more than strictly needed while building.
E.g. a build including a very large 1.3GB assembly, with several
native libraries embedded, save a lot of time avoiding the rewrites
mtouch (before)
Total time: 64202 ms
mtouch (after)
Total time: 34840 ms
* Add XM support for RemoveUserResourcesSubStep
* Tests supplied by @chamons