swift234

Use address projection instead of projection when expanding projection paths
for a SILType in MemLocation.

We get a sequence of address projections when initializing a memory location, i.e.
trace back to the base and then call getAddrProjectionPath.

To keep it consistent, we use address projections when we expand the projection
tree for a specific SILType as well.

By doing so, to get the type of the MemLocation, we can get just the first entry
in the projectionpath and get its object type.

Swift SVN r32775