Fix ast_to_text output to pass tests.

pkg/kernel/lib/text/ast_to_text.dart

Index: pkg/kernel/lib/text/ast_to_text.dart
diff --git a/pkg/kernel/lib/text/ast_to_text.dart b/pkg/kernel/lib/text/ast_to_text.dart
index d4e657574bafec04d5ffe7b40b6ad89d069ebc80..58f4f29f04e5101066e8646b51c75785538d9440 100644
--- a/pkg/kernel/lib/text/ast_to_text.dart
+++ b/pkg/kernel/lib/text/ast_to_text.dart
@@ -499,7 +499,8 @@ class Printer extends Visitor<Null> {
     if (function.asyncMarker != AsyncMarker.Sync) {
       writeSpaced(getAsyncMarkerKeyword(function.asyncMarker));
     }
-    if (function.dartAsyncMarker != AsyncMarker.Sync) {
+    if (function.dartAsyncMarker != AsyncMarker.Sync &&
+        function.dartAsyncMarker != function.asyncMarker) {
       writeSpaced("/* originally");
       writeSpaced(getAsyncMarkerKeyword(function.dartAsyncMarker));
       writeSpaced("*/");