[VM generic functions] Support generic async calls.

runtime/vm/ast_transformer.cc

Index: runtime/vm/ast_transformer.cc
diff --git a/runtime/vm/ast_transformer.cc b/runtime/vm/ast_transformer.cc
index a050e6cb20bed67f9f01140690f86469d1c79b1a..398e2cb9709b7ff2cf24cf2c1166052605541780 100644
--- a/runtime/vm/ast_transformer.cc
+++ b/runtime/vm/ast_transformer.cc
@@ -318,7 +318,8 @@ void AwaitTransformer::VisitConditionalExprNode(ConditionalExprNode* node) {
 }
 
 void AwaitTransformer::VisitArgumentListNode(ArgumentListNode* node) {
-  ArgumentListNode* new_args = new (Z) ArgumentListNode(node->token_pos());
+  ArgumentListNode* new_args =
+      new (Z) ArgumentListNode(node->token_pos(), node->type_arguments());
   for (intptr_t i = 0; i < node->length(); i++) {
     new_args->Add(Transform(node->NodeAt(i)));
   }