format parameter list (#27261)

packages/flutter_tools/lib/src/ios/simulators.dart

diff --git a/packages/flutter_tools/lib/src/ios/simulators.dart b/packages/flutter_tools/lib/src/ios/simulators.dart
index 90c2d67..525a1da 100644
--- a/packages/flutter_tools/lib/src/ios/simulators.dart
+++ b/packages/flutter_tools/lib/src/ios/simulators.dart
@@ -139,7 +139,7 @@
     return result;
   }
 
-  Future<RunResult> launch(String deviceId, String appIdentifier, [List<String> launchArgs]) {
+  Future<RunResult> launch(String deviceId, String appIdentifier, [ List<String> launchArgs ]) {
     final List<String> args = <String>[_xcrunPath, 'simctl', 'launch', deviceId, appIdentifier];
     if (launchArgs != null)
       args.addAll(launchArgs);
@@ -434,7 +434,7 @@
   }
 
   @override
-  DeviceLogReader getLogReader({ApplicationPackage app}) {
+  DeviceLogReader getLogReader({ ApplicationPackage app }) {
     assert(app is IOSApp);
     _logReaders ??= <ApplicationPackage, _IOSSimulatorLogReader>{};
     return _logReaders.putIfAbsent(app, () => _IOSSimulatorLogReader(this, app));
@@ -700,7 +700,7 @@
   }
 
   @override
-  Future<int> forward(int devicePort, {int hostPort}) async {
+  Future<int> forward(int devicePort, { int hostPort }) async {
     if (hostPort == null || hostPort == 0) {
       hostPort = devicePort;
     }