Clean App.framework, Generated.xcconfig, flutter_export_environment.sh (#51532)

packages/flutter_tools/lib/src/project.dart

diff --git a/packages/flutter_tools/lib/src/project.dart b/packages/flutter_tools/lib/src/project.dart
index 4a9944e..6da9674 100644
--- a/packages/flutter_tools/lib/src/project.dart
+++ b/packages/flutter_tools/lib/src/project.dart
@@ -567,6 +567,10 @@
     .childDirectory('Flutter')
     .childFile('Generated.xcconfig');
 
+  Directory get compiledDartFramework => _flutterLibRoot
+      .childDirectory('Flutter')
+      .childDirectory('App.framework');
+
   Directory get pluginRegistrantHost {
     return isModule
         ? _flutterLibRoot