[Sema] Use the right FoldingSet.

We were doing FindNodeOrInsertPos on SubstTemplateTypeParmPackTypes, so
we should presumably be inserting into SubstTemplateTypeParmPackTypes.

Looks like the FoldingSet API can be tweaked a bit so that we can catch
things like this at compile-time. I'll look into that shortly.

I'm unsure of how to test this; suggestions welcome.

Thanks to Vladimir Voskresensky for bringing this up!


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@305207 91177308-0d34-0410-b5e6-96231b3b80d8

lib/AST/ASTContext.cpp

@@ -3565,7 +3565,7 @@ QualType ASTContext::getSubstTemplateTypeParmPackType(
     = new (*this, TypeAlignment) SubstTemplateTypeParmPackType(Parm, Canon,
                                                                ArgPack);
   Types.push_back(SubstParm);
-  SubstTemplateTypeParmTypes.InsertNode(SubstParm, InsertPos);
+  SubstTemplateTypeParmPackTypes.InsertNode(SubstParm, InsertPos);
   return QualType(SubstParm, 0);  
 }