[flutter_releases] Flutter Dev 2.3.0-12.1.pre Framework Cherrypicks (#82852)

* enable uwp embedding in dev
* add tests
diff --git a/packages/flutter_tools/lib/src/features.dart b/packages/flutter_tools/lib/src/features.dart
index 079e8e4..f796a11 100644
--- a/packages/flutter_tools/lib/src/features.dart
+++ b/packages/flutter_tools/lib/src/features.dart
@@ -301,6 +301,10 @@
     available: true,
     enabledByDefault: false,
   ),
+  dev: FeatureChannelSetting(
+    available: true,
+    enabledByDefault: false,
+  ),
 );
 
 /// A [Feature] is a process for conditionally enabling tool features.
diff --git a/packages/flutter_tools/test/general.shard/features_test.dart b/packages/flutter_tools/test/general.shard/features_test.dart
index 1efeed5..c0d0469 100644
--- a/packages/flutter_tools/test/general.shard/features_test.dart
+++ b/packages/flutter_tools/test/general.shard/features_test.dart
@@ -467,6 +467,19 @@
       expect(featureFlags.isWindowsUwpEnabled, true);
     });
 
+    testWithoutContext('Flutter Windows UWP desktop off by default on dev', () {
+      final FeatureFlags featureFlags = createFlags('dev');
+
+      expect(featureFlags.isWindowsUwpEnabled, false);
+    });
+
+    testWithoutContext('Flutter Windows UWP desktop enabled with config on dev', () {
+      final FeatureFlags featureFlags = createFlags('dev');
+      testConfig.setValue('enable-windows-uwp-desktop', true);
+
+      expect(featureFlags.isWindowsUwpEnabled, true);
+    });
+
     testWithoutContext('Flutter Windows UWP desktop off by default on stable', () {
       final FeatureFlags featureFlags = createFlags('stable');