From 05225c1a6ddbc93fe8de358f9a98762029da3a44 Mon Sep 17 00:00:00 2001
From: David Iglesias Teixeira <ditman@gmail.com>
Date: Fri, 8 Mar 2024 12:43:16 -0800
Subject: [PATCH 1/5] Split the initialization the _flutter namespace and the
 loader object.

---
 lib/web_ui/flutter_js/src/flutter.js | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/lib/web_ui/flutter_js/src/flutter.js b/lib/web_ui/flutter_js/src/flutter.js
index 57208c7287129..4b381b60151f4 100644
--- a/lib/web_ui/flutter_js/src/flutter.js
+++ b/lib/web_ui/flutter_js/src/flutter.js
@@ -5,7 +5,9 @@
 import { FlutterLoader } from './loader.js';
 
 if (!window._flutter) {
-  window._flutter = {
-    loader: new FlutterLoader()
-  };
+  window._flutter = {};
+}
+
+if (!window._flutter.loader) {
+  window._flutter.loader = new FlutterLoader();
 }

From 7af7c2cb1d0416a7db8d52bd3356a379f286197c Mon Sep 17 00:00:00 2001
From: David Iglesias Teixeira <ditman@gmail.com>
Date: Fri, 8 Mar 2024 18:30:12 -0800
Subject: [PATCH 2/5] Ensure flutter.js can be defined after the _flutter
 namespace exists.

---
 lib/web_ui/dev/test_platform.dart | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/web_ui/dev/test_platform.dart b/lib/web_ui/dev/test_platform.dart
index 9c34e0c6c62d5..ab254a4e1cceb 100644
--- a/lib/web_ui/dev/test_platform.dart
+++ b/lib/web_ui/dev/test_platform.dart
@@ -554,13 +554,19 @@ class BrowserPlatform extends PlatformPlugin {
         (CompileConfiguration config) => _makeBuildConfigString(scriptBase, config)
       ).join(',\n');
       final String bootstrapScript = '''
-<script src="/flutter_js/flutter.js"></script>
 <script>
+  // Define this before flutter.js to test PR flutter/engine#51294
+  if (_flutter == null) {
+    _flutter = {};
+  }
   _flutter.buildConfig = {
     builds: [
       $buildConfigsString
     ]
   };
+</script>
+<script src="/flutter_js/flutter.js"></script>
+<script>
   _flutter.loader.load({
     config: {
       canvasKitBaseUrl: "/canvaskit/",

From 3794546f53004f08725e85a31a4de8a6e25ba60c Mon Sep 17 00:00:00 2001
From: David Iglesias Teixeira <ditman@gmail.com>
Date: Mon, 11 Mar 2024 10:36:12 -0700
Subject: [PATCH 3/5] Revert "Ensure flutter.js can be defined after the
 _flutter namespace exists."

This reverts commit 7af7c2cb1d0416a7db8d52bd3356a379f286197c.
---
 lib/web_ui/dev/test_platform.dart | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/lib/web_ui/dev/test_platform.dart b/lib/web_ui/dev/test_platform.dart
index ab254a4e1cceb..9c34e0c6c62d5 100644
--- a/lib/web_ui/dev/test_platform.dart
+++ b/lib/web_ui/dev/test_platform.dart
@@ -554,19 +554,13 @@ class BrowserPlatform extends PlatformPlugin {
         (CompileConfiguration config) => _makeBuildConfigString(scriptBase, config)
       ).join(',\n');
       final String bootstrapScript = '''
+<script src="/flutter_js/flutter.js"></script>
 <script>
-  // Define this before flutter.js to test PR flutter/engine#51294
-  if (_flutter == null) {
-    _flutter = {};
-  }
   _flutter.buildConfig = {
     builds: [
       $buildConfigsString
     ]
   };
-</script>
-<script src="/flutter_js/flutter.js"></script>
-<script>
   _flutter.loader.load({
     config: {
       canvasKitBaseUrl: "/canvaskit/",

From 58c319b7adce6f296bc2567fcc647c1c0045946c Mon Sep 17 00:00:00 2001
From: David Iglesias Teixeira <ditman@gmail.com>
Date: Mon, 11 Mar 2024 11:48:47 -0700
Subject: [PATCH 4/5] Reapply "Ensure flutter.js can be defined after the
 _flutter namespace exists."

This reverts commit 3794546f53004f08725e85a31a4de8a6e25ba60c.
---
 lib/web_ui/dev/test_platform.dart | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/web_ui/dev/test_platform.dart b/lib/web_ui/dev/test_platform.dart
index 9c34e0c6c62d5..ab254a4e1cceb 100644
--- a/lib/web_ui/dev/test_platform.dart
+++ b/lib/web_ui/dev/test_platform.dart
@@ -554,13 +554,19 @@ class BrowserPlatform extends PlatformPlugin {
         (CompileConfiguration config) => _makeBuildConfigString(scriptBase, config)
       ).join(',\n');
       final String bootstrapScript = '''
-<script src="/flutter_js/flutter.js"></script>
 <script>
+  // Define this before flutter.js to test PR flutter/engine#51294
+  if (_flutter == null) {
+    _flutter = {};
+  }
   _flutter.buildConfig = {
     builds: [
       $buildConfigsString
     ]
   };
+</script>
+<script src="/flutter_js/flutter.js"></script>
+<script>
   _flutter.loader.load({
     config: {
       canvasKitBaseUrl: "/canvaskit/",

From 8098d71f99c6690a861541e298ad443bc2257513 Mon Sep 17 00:00:00 2001
From: David Iglesias Teixeira <ditman@gmail.com>
Date: Mon, 11 Mar 2024 15:40:21 -0700
Subject: [PATCH 5/5] Ensure _flutter is defined before flutter.js loads.

---
 lib/web_ui/dev/test_platform.dart | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/lib/web_ui/dev/test_platform.dart b/lib/web_ui/dev/test_platform.dart
index ab254a4e1cceb..aa6d53c5959b6 100644
--- a/lib/web_ui/dev/test_platform.dart
+++ b/lib/web_ui/dev/test_platform.dart
@@ -555,10 +555,12 @@ class BrowserPlatform extends PlatformPlugin {
       ).join(',\n');
       final String bootstrapScript = '''
 <script>
-  // Define this before flutter.js to test PR flutter/engine#51294
-  if (_flutter == null) {
-    _flutter = {};
+  // Define this before loading flutter.js to test PR flutter/engine#51294
+  if (!window._flutter) {
+    window._flutter = {};
   }
+</script>
+<script>
   _flutter.buildConfig = {
     builds: [
       $buildConfigsString