add warning for deprecated .analysis_options file name

pkg/analyzer/test/src/task/options_test.dart

Index: pkg/analyzer/test/src/task/options_test.dart
diff --git a/pkg/analyzer/test/src/task/options_test.dart b/pkg/analyzer/test/src/task/options_test.dart
index 01ece33608643fadae7691a6e386fc36020cf415..98e022b5bbbaab73273ddd6db4bd148d6e4df5fd 100644
--- a/pkg/analyzer/test/src/task/options_test.dart
+++ b/pkg/analyzer/test/src/task/options_test.dart
@@ -143,18 +143,23 @@ analyzer:
 
 @reflectiveTest
 class GenerateNewOptionsErrorsTaskTest extends GenerateOptionsErrorsTaskTest {
+  bool get isOptionsFileDeprecated => false;
   String get optionsFilePath => '/${AnalysisEngine.ANALYSIS_OPTIONS_YAML_FILE}';
 }
 
 @reflectiveTest
 class GenerateOldOptionsErrorsTaskTest extends GenerateOptionsErrorsTaskTest {
+  bool get isOptionsFileDeprecated => true;
   String get optionsFilePath => '/${AnalysisEngine.ANALYSIS_OPTIONS_FILE}';
 }
 
 abstract class GenerateOptionsErrorsTaskTest extends AbstractContextTest {
   Source source;
 
+  bool get isOptionsFileDeprecated;
+
   String get optionsFilePath;
+
   LineInfo lineInfo(String source) =>
       GenerateOptionsErrorsTask.computeLineInfo(source);
 
@@ -211,6 +216,29 @@ abstract class GenerateOptionsErrorsTaskTest extends AbstractContextTest {
     expect(descriptor, isNotNull);
   }
 
+  @override
+  void computeResult(AnalysisTarget target, ResultDescriptor result,
+      {isInstanceOf matcher: null}) {
+    super.computeResult(target, result, matcher: matcher);
+    if (isOptionsFileDeprecated) {
+      bool found = false;
+      var errors = outputs[ANALYSIS_OPTIONS_ERRORS] as List<dynamic>;
+      for (var error in errors) {
+        if (error is AnalysisError &&
+            error.errorCode ==
+                AnalysisOptionsWarningCode
+                    .DEPRECATED_ANALYSIS_OPTIONS_FILE_NAME) {
+          errors.remove(error);
+          found = true;
+          break;
+        }
+      }
+      if (!found) {
+        fail('Expected deprecated analysis options file name warning');
+      }
+    }
+  }
+
   test_perform_bad_yaml() {
     String code = r'''
 :