gracefully degrade if lints option not defined

pkg/analyzer/lib/src/command_line/arguments.dart

Index: pkg/analyzer/lib/src/command_line/arguments.dart
diff --git a/pkg/analyzer/lib/src/command_line/arguments.dart b/pkg/analyzer/lib/src/command_line/arguments.dart
index 385b94b67803108d7407db66db92a12dff2251da..e0ab6761474ece69175ff18563183d37de7b8880 100644
--- a/pkg/analyzer/lib/src/command_line/arguments.dart
+++ b/pkg/analyzer/lib/src/command_line/arguments.dart
@@ -48,8 +48,12 @@ void applyAnalysisOptionFlags(AnalysisOptionsImpl options, ArgResults args) {
   if (args.wasParsed(strongModeFlag)) {
     options.strongMode = args[strongModeFlag];
   }
-  if (args.wasParsed(lintsFlag)) {
-    options.lint = args[lintsFlag];
+  try {
+    if (args.wasParsed(lintsFlag)) {
+      options.lint = args[lintsFlag];
+    }
+  } on ArgumentError {
+    // lints were not defined - ignore and fall through
   }
 }