Handle potential null value in setUpChromeConsoleListeners (#2162)

Author: elliette

dwds/CHANGELOG.md

@@ -1,5 +1,7 @@
 ## 19.0.2-wip
 
+- Fix Flutter crash due to potential null value in `setUpChromeConsoleListener`. - [#2162](https://github.com/dart-lang/webdev/pull/2162)
+
 ## 19.0.1
 
 - Do not show async frame errors on evaluation. - [#2073](https://github.com/dart-lang/webdev/pull/2073)

dwds/lib/src/services/chrome_proxy_service.dart

@@ -1361,7 +1361,8 @@ ${globalLoadStrategy.loadModuleSnippet}("dart_sdk").developer.invokeExtension(
       final isolate = inspector.isolate;
       if (isolateRef.id != isolate.id) return;
 
-      final firstArgValue = event.args[0].value as String;
+      final args = event.args;
+      final firstArgValue = (args.isNotEmpty ? args[0].value : null) as String?;
       // TODO(nshahan) - Migrate 'inspect' and 'log' events to the injected
       // client communication approach as well?
       switch (firstArgValue) {