Fix formatting (#121167)

packages/flutter/lib/src/material/tab_controller.dart

@@ -101,8 +101,12 @@ class TabController extends ChangeNotifier {
   ///
   /// The `initialIndex` must be valid given [length] and must not be null. If
   /// [length] is zero, then `initialIndex` must be 0 (the default).
-  TabController({ int initialIndex = 0, Duration? animationDuration, required this.length, required TickerProvider vsync})
-    : assert(length >= 0),
+  TabController({
+    int initialIndex = 0,
+    Duration? animationDuration,
+    required this.length,
+    required TickerProvider vsync,
+  }) : assert(length >= 0),
        assert(initialIndex >= 0 && (length == 0 || initialIndex < length)),
        _index = initialIndex,
        _previousIndex = initialIndex,