Log only valid occurences of 'All native types used ...'.

tests/compiler/dart2js/diagnostic_helper.dart

Index: tests/compiler/dart2js/diagnostic_helper.dart
diff --git a/tests/compiler/dart2js/diagnostic_helper.dart b/tests/compiler/dart2js/diagnostic_helper.dart
index 7d82a3d4677d5e4f9620e28d051ce42879274cac..6f63e8a3a859fc1a7eb272eaf3afe5b70c1b9975 100644
--- a/tests/compiler/dart2js/diagnostic_helper.dart
+++ b/tests/compiler/dart2js/diagnostic_helper.dart
@@ -65,6 +65,10 @@ class DiagnosticCollector implements CompilerDiagnostics {
     return filterMessagesByKinds([Diagnostic.CRASH]);
   }
 
+  Iterable<CollectedMessage> get verboseInfos {
+    return filterMessagesByKinds([Diagnostic.VERBOSE_INFO]);
+  }
+
   /// `true` if non-verbose messages has been collected.
   bool get hasRegularMessages {
     return messages.any((m) => m.kind != Diagnostic.VERBOSE_INFO);