Convert top-level inference errors to hints

pkg/analyzer/test/src/task/strong/strong_test_helper.dart

Index: pkg/analyzer/test/src/task/strong/strong_test_helper.dart
diff --git a/pkg/analyzer/test/src/task/strong/strong_test_helper.dart b/pkg/analyzer/test/src/task/strong/strong_test_helper.dart
index dddce076a27577ce1f2abebc618266b6198165fe..77f38a3a5447654db5fc0d7b205e505b0c7ed8f8 100644
--- a/pkg/analyzer/test/src/task/strong/strong_test_helper.dart
+++ b/pkg/analyzer/test/src/task/strong/strong_test_helper.dart
@@ -67,6 +67,11 @@ String _errorCodeName(ErrorCode errorCode) {
 
 ErrorSeverity _errorSeverity(
     AnalysisOptions analysisOptions, AnalysisError error) {
+  // TODO(brianwilkerson) Remove the if when top-level inference is made an
+  // error again.
+  if (error.errorCode.name.startsWith('STRONG_MODE_TOP_LEVEL_')) {
+    return ErrorSeverity.ERROR;
+  }
   return ErrorProcessor.getProcessor(analysisOptions, error)?.severity ??
       error.errorCode.errorSeverity;
 }