Reinstate SubstitutionList-based printing for SIL and specialized conformances.

The SIL parser depends on these, still.

Author: DougGregor

lib/AST/ASTPrinter.cpp

@@ -4157,14 +4157,8 @@ void ProtocolConformance::printName(llvm::raw_ostream &os,
   case ProtocolConformanceKind::Specialized: {
     auto spec = cast<SpecializedProtocolConformance>(this);
     os << "specialize <";
-    auto subMap = spec->getSubstitutionMap();
-    auto genericParams =
-      spec->getGenericConformance()->getGenericSignature()->getGenericParams();
-    interleave(genericParams,
-               [&](Type type) {
-                 type.subst(subMap).print(os, PO);
-
-               },
+    interleave(spec->getSubstitutionMap().toList(),
+               [&](const Substitution &s) { s.print(os, PO); },
                [&] { os << ", "; });
 
     os << "> (";

lib/SIL/SILPrinter.cpp

@@ -1066,15 +1066,7 @@ class SILPrinter : public SILInstructionVisitor<SILPrinter> {
   }
 
   void printSubstitutions(SubstitutionMap Subs) {
-    if (Subs.empty())
-      return;
-
-    *this << '<';
-    interleave(Subs.getReplacementTypes(),
-               [&](Type type) { *this << type; },
-               [&] { *this << ", "; });
-    *this << '>';
-
+    printSubstitutions(Subs.toList());
   }
 
   void printSubstitutions(SubstitutionList Subs) {