CLI support for `enableAssertInitializer`s.

pkg/analyzer_cli/test/options_test.dart

Index: pkg/analyzer_cli/test/options_test.dart
diff --git a/pkg/analyzer_cli/test/options_test.dart b/pkg/analyzer_cli/test/options_test.dart
index fe340330091e38f1c07e4693923f07d7cff56c92..278aac9cecf564801f997ecd30068c28ea7d97e1 100644
--- a/pkg/analyzer_cli/test/options_test.dart
+++ b/pkg/analyzer_cli/test/options_test.dart
@@ -35,6 +35,7 @@ main() {
         expect(options.enableStrictCallChecks, isFalse);
         expect(options.enableSuperMixins, isFalse);
         expect(options.enableTypeChecks, isFalse);
+        expect(options.enableAssertInitializer, isFalse);
         expect(options.hintsAreFatal, isFalse);
         expect(options.ignoreUnrecognizedFlags, isFalse);
         expect(options.log, isFalse);
@@ -86,6 +87,12 @@ main() {
         expect(options.enableTypeChecks, isTrue);
       });
 
+      test('enable assert initializers', () {
+        CommandLineOptions options = CommandLineOptions.parse(
+            ['--dart-sdk', '.', '--enable-assert-initializers', 'foo.dart']);
+        expect(options.enableAssertInitializer, isTrue);
+      });
+
       test('hintsAreFatal', () {
         CommandLineOptions options = CommandLineOptions
             .parse(['--dart-sdk', '.', '--fatal-hints', 'foo.dart']);