From b9b83f2112501b25bf55cb3a0db2f221998f1eae Mon Sep 17 00:00:00 2001
From: Sam Rawlins <srawlins@google.com>
Date: Thu, 14 Jan 2021 14:29:58 -0800
Subject: [PATCH] Return null in Future<WebSocketChannel>.catchError handler
 (flutter/engine#23101)

---
 engine/src/flutter/lib/web_ui/dev/test_platform.dart | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/engine/src/flutter/lib/web_ui/dev/test_platform.dart b/engine/src/flutter/lib/web_ui/dev/test_platform.dart
index 330457c23b4..8e181eab37e 100644
--- a/engine/src/flutter/lib/web_ui/dev/test_platform.dart
+++ b/engine/src/flutter/lib/web_ui/dev/test_platform.dart
@@ -559,7 +559,7 @@ class BrowserManager {
     }).catchError((dynamic error, StackTrace stackTrace) {
       browser.close();
       if (completer.isCompleted) {
-        return;
+        return null;
       }
       completer.completeError(error, stackTrace);
     });