Check that localization files of stocks app are up-to-date (#161608)

Fixes https://github.com/flutter/flutter/issues/160473

.ci.yaml

@@ -389,7 +389,6 @@ targets:
   - name: Linux packages_autoroller
     presubmit: false
     recipe: pub_autoroller/pub_autoroller
-    bringup: true # https://github.com/flutter/flutter/issues/160473
     # This takes a while because we need to fetch network dependencies and run
     # Gradle for every android app in the repo
     timeout: 45

dev/benchmarks/test_apps/stocks/l10n.yaml

@@ -20,3 +20,5 @@ template-arb-file: stocks_en.arb
 ## StockStrings getter. This removes the need for adding null checks
 ## in the Flutter application itself.
 nullable-getter: false
+## Run the formatter on the generated localization files.
+format: true

dev/bots/analyze.dart

@@ -152,6 +152,9 @@ Future<void> run(List<String> arguments) async {
   printProgress('Internationalization...');
   await verifyInternationalizations(flutterRoot, dart);
 
+  printProgress('Localization files of stocks app...');
+  await verifyStockAppLocalizations(flutterRoot);
+
   printProgress('Integration test timeouts...');
   await verifyIntegrationTestTimeouts(flutterRoot);
 
@@ -1312,6 +1315,49 @@ Future<void> verifyInternationalizations(String workingDirectory, String dartExe
   }
 }
 
+Future<void> verifyStockAppLocalizations(String workingDirectory) async {
+  final Directory appRoot = Directory(
+    path.join(workingDirectory, 'dev', 'benchmarks', 'test_apps', 'stocks'),
+  );
+  if (!appRoot.existsSync()) {
+    foundError(<String>['Stocks app does not exist at expected location: ${appRoot.path}']);
+  }
+
+  // Regenerate the localizations.
+  final String flutterExecutable = path.join(
+    workingDirectory,
+    'bin',
+    'flutter${Platform.isWindows ? '.bat' : ''}',
+  );
+  await _evalCommand(flutterExecutable, const <String>['gen-l10n'], workingDirectory: appRoot.path);
+  final Directory i10nDirectory = Directory(path.join(appRoot.path, 'lib', 'i18n'));
+  if (!i10nDirectory.existsSync()) {
+    foundError(<String>[
+      'Localization files for stocks app not found at expected location: ${i10nDirectory.path}',
+    ]);
+  }
+
+  // Check that regeneration did not dirty the tree.
+  final EvalResult result = await _evalCommand('git', <String>[
+    'diff',
+    '--name-only',
+    '--exit-code',
+    i10nDirectory.path,
+  ], workingDirectory: workingDirectory);
+  if (result.exitCode == 1) {
+    foundError(<String>[
+      'The following localization files for the stocks app appear to be out of date:',
+      ...(const LineSplitter().convert(result.stdout).map((String line) => ' * $line')),
+      'Run "flutter gen-l10n" in "${path.relative(appRoot.path, from: workingDirectory)}" to regenerate.',
+    ]);
+  } else if (result.exitCode != 0) {
+    foundError(<String>[
+      'Failed to run "git diff" on localization files of stocks app:',
+      result.stderr,
+    ]);
+  }
+}
+
 /// Verifies that all instances of "checked mode" have been migrated to "debug mode".
 Future<void> verifyNoCheckedMode(String workingDirectory) async {
   final String flutterPackages = path.join(workingDirectory, 'packages');