This will pave the way to introduce a full fledged symbol visitor
similar to how we have a type visitor, thus allowing the same
dumping code to be used in llvm-readobj and llvm-pdbdump.
Differential Revision: http://reviews.llvm.org/D20384
Reviewed By: rnk
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270475 91177308-0d34-0410-b5e6-96231b3b80d8