instead of just using "unsigned". This gives us more flexibility in changing
the definition of the handle later, and is more self-documenting.
Added tracking of block stack in the Deserializer. Now clients can query
if they are still within a block using the methods GetCurrentBlockLocation()
and FinishedBlock().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43903 91177308-0d34-0410-b5e6-96231b3b80d8
