some formatting of map, parameters and spaces (#29760)

diff --git a/packages/flutter_tools/lib/src/android/android_sdk.dart b/packages/flutter_tools/lib/src/android/android_sdk.dart
index 5c66f96..d8a7326 100644
--- a/packages/flutter_tools/lib/src/android/android_sdk.dart
+++ b/packages/flutter_tools/lib/src/android/android_sdk.dart
@@ -588,7 +588,8 @@
 }
 
 class AndroidSdkVersion implements Comparable<AndroidSdkVersion> {
-  AndroidSdkVersion._(this.sdk, {
+  AndroidSdkVersion._(
+    this.sdk, {
     @required this.sdkLevel,
     @required this.platformName,
     @required this.buildToolsVersion,