[PGO] Convert InstrProfRecord based serialization methods to use common C methods

1. Convert serialization methods using InstrProfRecord as source into C (impl)
   interfaces using Closure.
2. Reimplement InstrProfRecord serialization method to use new C interface
   as dummy wrapper. 

Now it is ready to implement wrapper for runtime value profile data.

(The new code need better source location -- but not changed in this patch to
 minimize diffs. )

llvm-svn: 254057