Only print function member declarations and skip the bodies since the bodies are already represented in SIL and ASTPrinter is not good enough to print arbitrary expressions.
In order to have valid output, make sure that ASTPrinter does not print references to DynamicLookup protocol.
Swift SVN r8627
These types are really the same for the type checker, so they are printed in
exactly the same way. To recover the original spelling, prefer to print
a TypeRepr, if available.
Swift SVN r8603