new handleInvalidTopLevelDeclaration event in fasta parser

pkg/front_end/lib/src/fasta/parser/parser.dart

Index: pkg/front_end/lib/src/fasta/parser/parser.dart
diff --git a/pkg/front_end/lib/src/fasta/parser/parser.dart b/pkg/front_end/lib/src/fasta/parser/parser.dart
index c2b8fc7e204337cca87f4e47f67fc40b4ec0a374..f7e2e1f90c1ca2e2ecc07d131512ef7aaa3a7661 100644
--- a/pkg/front_end/lib/src/fasta/parser/parser.dart
+++ b/pkg/front_end/lib/src/fasta/parser/parser.dart
@@ -261,8 +261,12 @@ class Parser {
       return parseExport(token);
     } else if (identical(value, 'part')) {
       return parsePartOrPartOf(token);
-    } else {
+    } else if (token.type == TokenType.IDENTIFIER || token.keyword != null) {
       return parseTopLevelMember(token);
+    } else {
+      reportRecoverableErrorWithToken(token, fasta.templateExpectedDeclaration);
+      listener.handleInvalidTopLevelDeclaration(token);
+      return token.next;
     }
   }