Support for flutter run/build module on iOS (#21216)

packages/flutter_tools/lib/src/flutter_manifest.dart

diff --git a/packages/flutter_tools/lib/src/flutter_manifest.dart b/packages/flutter_tools/lib/src/flutter_manifest.dart
index 81a1e64..60b3fb3 100644
--- a/packages/flutter_tools/lib/src/flutter_manifest.dart
+++ b/packages/flutter_tools/lib/src/flutter_manifest.dart
@@ -140,6 +140,14 @@
     return null;
   }
 
+  /// Returns the iOS bundle identifier declared by this manifest in its
+  /// module descriptor. Returns null, if there is no such declaration.
+  String get iosBundleIdentifier {
+    if (isModule)
+      return _flutterDescriptor['module']['iosBundleIdentifier'];
+    return null;
+  }
+
   List<Map<String, dynamic>> get fontsDescriptor {
     final List<dynamic> fontList = _flutterDescriptor['fonts'];
     return fontList == null