[flutter_plugin_tools] Check licenses in Kotlin

packages/shared_preferences/shared_preferences/example/android/app/src/main/kotlin/io/flutter/plugins/example/MainActivity.kt

@@ -1,3 +1,7 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
 package io.flutter.plugins.example
 
 import io.flutter.embedding.android.FlutterActivity

script/tool/CHANGELOG.md

@@ -9,6 +9,7 @@
 - Added flags to `version-check` to allow overriding the platform interface
   major version change restriction.
 - Improved error handling and error messages in CHANGELOG version checks.
+- `license-check` now validates Kotlin files.
 
 ## 0.7.1
 

script/tool/lib/src/license_check_command.dart

@@ -16,6 +16,7 @@ const Set<String> _codeFileExtensions = <String>{
   '.h',
   '.html',
   '.java',
+  '.kt',
   '.m',
   '.mm',
   '.swift',

script/tool/test/license_check_command_test.dart

@@ -66,6 +66,7 @@ void main() {
         'html': true,
         'java': true,
         'json': false,
+        'kt': true,
         'm': true,
         'md': false,
         'mm': true,