When I created a new flutter app, the content of android\app\build.gradle is
...
defaultConfig {
// TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
applicationId "com.example.app_name"
minSdkVersion flutter.minSdkVersion
targetSdkVersion flutter.targetSdkVersion
versionCode flutterVersionCode.toInteger()
versionName flutterVersionName
}
...
What is flutter.minSdkVersion? Where it comes from? How do we know the actual value of it?

flutter/packages/flutter_tools/gradle/flutter.gradle