Selenium / Dartium cleanup

tools/testing/dart/test_options.dart

Index: tools/testing/dart/test_options.dart
diff --git a/tools/testing/dart/test_options.dart b/tools/testing/dart/test_options.dart
index a9d419a9cd0261123a777a4cb4c6d9d40bb467f2..8dad0ce5f915713a4beac977cfec877f8378a10b 100644
--- a/tools/testing/dart/test_options.dart
+++ b/tools/testing/dart/test_options.dart
@@ -415,6 +415,14 @@ is 'dart file.dart' and you specify special command
       print("Error: shard index is ${config['shard']} out of " + 
             "${config['shards']} shards");
     }
+    if (config['runtime'] == 'dartium' && config['compiler'] == 'none' &&
+        config['checked']) {
+      // TODO(vsm): Set the DART_FLAGS environment appropriately when
+      // invoking Selenium to support checked mode.  It's not clear
+      // the current selenium API supports this.
+      isValid = false;
+      print("Warning: checked mode is not yet supported for dartium tests.");
+    }
     return isValid;
   }