From 9fcc2f0a9475fcec1e1070bbf2e5dade03b21168 Mon Sep 17 00:00:00 2001
From: Chris Bracken <chris@bracken.jp>
Date: Thu, 20 Dec 2018 12:06:26 -0800
Subject: [PATCH] [License] Enable prefer_final_fields lint

---
 engine/src/flutter/tools/licenses/analysis_options.yaml | 1 +
 engine/src/flutter/tools/licenses/lib/filesystem.dart   | 4 ++--
 engine/src/flutter/tools/licenses/lib/licenses.dart     | 4 ++--
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/engine/src/flutter/tools/licenses/analysis_options.yaml b/engine/src/flutter/tools/licenses/analysis_options.yaml
index d3dfa75eec..9ad2263657 100644
--- a/engine/src/flutter/tools/licenses/analysis_options.yaml
+++ b/engine/src/flutter/tools/licenses/analysis_options.yaml
@@ -47,6 +47,7 @@ linter:
     - package_prefixed_library_names
     - prefer_asserts_in_initializer_lists
     - prefer_equal_for_default_values
+    - prefer_final_fields
     - prefer_final_locals
     - prefer_is_not_empty
     - prefer_single_quotes
diff --git a/engine/src/flutter/tools/licenses/lib/filesystem.dart b/engine/src/flutter/tools/licenses/lib/filesystem.dart
index d11d0d0608..27034b57ab 100644
--- a/engine/src/flutter/tools/licenses/lib/filesystem.dart
+++ b/engine/src/flutter/tools/licenses/lib/filesystem.dart
@@ -530,8 +530,8 @@ class ArchiveDirectory extends IoNode implements Directory {
   @override
   final String name;
 
-  Map<String, ArchiveDirectory> _subdirectories = SplayTreeMap<String, ArchiveDirectory>();
-  List<ArchiveFile> _files = <ArchiveFile>[];
+  final Map<String, ArchiveDirectory> _subdirectories = SplayTreeMap<String, ArchiveDirectory>();
+  final List<ArchiveFile> _files = <ArchiveFile>[];
 
   void _add(a.ArchiveFile entry, List<String> remainingPath) {
     if (remainingPath.length > 1) {
diff --git a/engine/src/flutter/tools/licenses/lib/licenses.dart b/engine/src/flutter/tools/licenses/lib/licenses.dart
index 030dc080df..fec29c4d80 100644
--- a/engine/src/flutter/tools/licenses/lib/licenses.dart
+++ b/engine/src/flutter/tools/licenses/lib/licenses.dart
@@ -368,8 +368,8 @@ abstract class License implements Comparable<License> {
   final LicenseType type;
 
   Iterable<String> get licensees => _licensees;
-  List<String> _licensees = <String>[];
-  Set<String> _libraries = Set<String>();
+  final List<String> _licensees = <String>[];
+  final Set<String> _libraries = Set<String>();
 
   bool get isUsed => _licensees.isNotEmpty;