Add a hint to rename .analysis_options files.

pkg/analyzer/lib/src/task/options.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer.src.task.options;
 
 import 'dart:collection';
 
 import 'package:analyzer/analyzer.dart';
 import 'package:analyzer/plugin/options.dart';
@@ skipping 393 matching lines @@
     new AnalyzerOptionsValidator(),
     new LinterOptionsValidator(),
     new LinterRuleOptionsValidator()
   ];
 
   OptionsFileValidator(this.source);
 
   List<AnalysisError> validate(Map<String, YamlNode> options) {
     RecordingErrorListener recorder = new RecordingErrorListener();
     ErrorReporter reporter = new ErrorReporter(recorder, source);
+    if (AnalysisEngine.ANALYSIS_OPTIONS_FILE == source.shortName) {
+      reporter.reportError(new AnalysisError(
+          source,
+          0, // offset
+          1, // length
+          AnalysisOptionsHintCode.DEPRECATED_ANALYSIS_OPTIONS_FILE_NAME,
+          [source.shortName]));
+    }
     _validators.forEach((OptionsValidator v) => v.validate(reporter, options));
     return recorder.errors;
   }
 }
 
 /// Validates `analyzer` strong-mode value configuration options.
 class StrongModeOptionValueValidator extends OptionsValidator {
   ErrorBuilder trueOrFalseBuilder = new TrueOrFalseValueErrorBuilder();
 
   @override
@@ skipping 191 matching lines @@
         }
       });
     } else if (config is Map) {
       options.strongMode = true;
       config.forEach((k, v) => _applyStrongModeOption(options, k, v));
     } else {
       options.strongMode = config is bool ? config : false;
     }
   }
 }