Allow Analysis Server crawl up the folders to search .analysis_options file.

pkg/analysis_server/lib/src/context_manager.dart

Index: pkg/analysis_server/lib/src/context_manager.dart
diff --git a/pkg/analysis_server/lib/src/context_manager.dart b/pkg/analysis_server/lib/src/context_manager.dart
index 4ce26ae17d3688c44a5fee768c06dacba82fe77c..fc2573c3f27d0948e2a058e526c54035a4b8b142 100644
--- a/pkg/analysis_server/lib/src/context_manager.dart
+++ b/pkg/analysis_server/lib/src/context_manager.dart
@@ -637,13 +637,13 @@ class ContextManagerImpl implements ContextManager {
   }
 
   /**
-   * Return the options from the analysis options file in the given [folder], or
-   * `null` if there is no file in the folder or if the contents of the file are
-   * not valid YAML.
+   * Return the options from the analysis options file in the given [folder]
+   * if exists, or in one of the parent folders, or `null` if no analysis
+   * options file is found or if the contents of the file are not valid YAML.
    */
   Map<String, Object> readOptions(Folder folder) {
     try {
-      return analysisOptionsProvider.getOptions(folder);
+      return analysisOptionsProvider.getOptions(folder, crawlUp: true);
     } catch (_) {
       // Parse errors are reported by GenerateOptionsErrorsTask.
     }