Report error on only-try block.

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 38b20a2bc6040b34748a555c040649c676a0fdc6..652d5c252aafcc83fa3aa022b4548166c23da0e1 100644
--- a/pkg/front_end/lib/src/fasta/parser/parser.dart
+++ b/pkg/front_end/lib/src/fasta/parser/parser.dart
@@ -3487,6 +3487,10 @@ class Parser {
       finallyKeyword = token;
       token = parseBlock(token.next);
       listener.handleFinallyBlock(finallyKeyword);
+    } else {
+      if (catchCount == 0) {
+        reportRecoverableError(tryKeyword, ErrorKind.OnlyTry);
+      }
     }
     listener.endTryStatement(catchCount, tryKeyword, finallyKeyword);
     return token;