From fdb7bd3c0fcf4cb62d959aa495aaa9733574ca4d Mon Sep 17 00:00:00 2001
From: Jonah Williams <jonahwilliams@google.com>
Date: Tue, 10 Mar 2020 12:09:37 -0700
Subject: [PATCH] [flutter_tools] attempt to fix .first crasher in web loading
 (#52301)

---
 packages/flutter_tools/lib/src/web/chrome.dart | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/packages/flutter_tools/lib/src/web/chrome.dart b/packages/flutter_tools/lib/src/web/chrome.dart
index 19166dabf6d..55a998bcd49 100644
--- a/packages/flutter_tools/lib/src/web/chrome.dart
+++ b/packages/flutter_tools/lib/src/web/chrome.dart
@@ -234,6 +234,9 @@ class ChromeLauncher {
       final HttpClientRequest request = await client.getUrl(base.resolve('/json/list'));
       final HttpClientResponse response = await request.close();
       final List<dynamic> jsonObject = await json.fuse(utf8).decoder.bind(response).single as List<dynamic>;
+      if (jsonObject == null || jsonObject.isEmpty) {
+        return base;
+      }
       return base.resolve(jsonObject.first['devtoolsFrontendUrl'] as String);
     } on Exception {
       // If we fail to talk to the remote debugger protocol, give up and return