AST: Print @_typeSequence in the ASTPrinter

Author: slavapestov

lib/AST/ASTPrinter.cpp

@@ -1679,6 +1679,9 @@ void PrintAST::printSingleDepthOfGenericSignature(
     llvm::interleave(
         genericParams,
         [&](GenericTypeParamType *param) {
+          if (param->isTypeSequence())
+            Printer.printAttrName("@_typeSequence ");
+
           if (!subMap.empty()) {
             printType(substParam(param));
           } else if (auto *GP = param->getDecl()) {
@@ -3473,6 +3476,8 @@ void PrintAST::visitTypeAliasDecl(TypeAliasDecl *decl) {
 
 void PrintAST::visitGenericTypeParamDecl(GenericTypeParamDecl *decl) {
   recordDeclLoc(decl, [&] {
+    if (decl->isTypeSequence())
+      Printer.printAttrName("@_typeSequence ");
     Printer.printName(decl->getName(), PrintNameContext::GenericParameter);
   });