remove listDartSources (#43950)

packages/flutter_tools/lib/src/build_system/targets/dart.dart

@@ -8,10 +8,8 @@ import '../../artifacts.dart';
 import '../../asset.dart';
 import '../../base/build.dart';
 import '../../base/file_system.dart';
-import '../../base/platform.dart';
 import '../../build_info.dart';
 import '../../compile.dart';
-import '../../dart/package_map.dart';
 import '../../devfs.dart';
 import '../../globals.dart';
 import '../../project.dart';
@@ -42,27 +40,6 @@ const String kTrackWidgetCreation = 'TrackWidgetCreation';
 /// The other supported value is armv7, the 32-bit iOS architecture.
 const String kIosArchs = 'IosArchs';
 
-/// Finds the locations of all dart files within the project.
-///
-/// This does not attempt to determine if a file is used or imported, so it
-/// may otherwise report more files than strictly necessary.
-List<File> listDartSources(Environment environment) {
-  final Map<String, Uri> packageMap = PackageMap(environment.projectDir.childFile('.packages').path).map;
-  final List<File> dartFiles = <File>[];
-  for (Uri uri in packageMap.values) {
-    final Directory libDirectory = fs.directory(uri.toFilePath(windows: platform.isWindows));
-    if (!libDirectory.existsSync()) {
-      continue;
-    }
-    for (FileSystemEntity entity in libDirectory.listSync(recursive: true)) {
-      if (entity is File && entity.path.endsWith('.dart')) {
-        dartFiles.add(entity);
-      }
-    }
-  }
-  return dartFiles;
-}
-
 /// Copies the prebuilt flutter bundle.
 // This is a one-off rule for implementing build bundle in terms of assemble.
 class CopyFlutterBundle extends Target {

packages/flutter_tools/test/general.shard/build_system/targets/dart_test.dart

@@ -354,16 +354,6 @@ flutter_tools:lib/''');
     ProcessManager: () => mockProcessManager,
   }));
 
-  test('list dart sources handles packages without lib directories', () => testbed.run(() {
-    fs.file('.packages')
-      ..createSync()
-      ..writeAsStringSync('''
-# Generated
-example:fiz/lib/''');
-    fs.directory('fiz').createSync();
-    expect(listDartSources(androidEnvironment), <File>[]);
-  }));
-
   test('Profile/ReleaseCopyFlutterAotBundle copies .so to correct output directory', () => testbed.run(() async {
     androidEnvironment.buildDir.createSync(recursive: true);
     androidEnvironment.buildDir.childFile('app.so').createSync();