Add support for watch events and error notifications

pkg/analysis_server/test/context_manager_test.dart

Index: pkg/analysis_server/test/context_manager_test.dart
diff --git a/pkg/analysis_server/test/context_manager_test.dart b/pkg/analysis_server/test/context_manager_test.dart
index c928026a38eeef69fcca3ed6e59dfe81d4a1fe3b..96db4e210cede7d0cd2554b2b9bb97677662aeee 100644
--- a/pkg/analysis_server/test/context_manager_test.dart
+++ b/pkg/analysis_server/test/context_manager_test.dart
@@ -4,6 +4,7 @@
 
 library test.context.directory.manager;
 
+import 'dart:async';
 import 'dart:collection';
 
 import 'package:analysis_server/src/context_manager.dart';
@@ -33,6 +34,7 @@ import 'package:plugin/manager.dart';
 import 'package:plugin/plugin.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
+import 'package:watcher/watcher.dart';
 
 import 'mock_sdk.dart';
 import 'mocks.dart';
@@ -2598,6 +2600,14 @@ analyzer:
     // Verify that analysis options was parsed and strong-mode set.
     expect(analysisOptions.strongMode, true);
   }
+
+  test_watchEvents() async {
+    String libPath = newFolder([projPath, ContextManagerTest.LIB_NAME]);
+    manager.setRoots(<String>[projPath], <String>[], <String, String>{});
+    newFile([libPath, 'main.dart']);
+    await new Future.delayed(new Duration(milliseconds: 1));
+    expect(callbacks.watchEvents, hasLength(1));
+  }
 }
 
 class TestContextManagerCallbacks extends ContextManagerCallbacks {
@@ -2664,6 +2674,11 @@ class TestContextManagerCallbacks extends ContextManagerCallbacks {
    */
   List<String> lastFlushedFiles;
 
+  /**
+   * The watch events that have been broadcast.
+   */
+  List<WatchEvent> watchEvents = <WatchEvent>[];
+
   TestContextManagerCallbacks(
       this.resourceProvider, this.sdkManager, this.logger, this.scheduler);
 
@@ -2802,6 +2817,11 @@ class TestContextManagerCallbacks extends ContextManagerCallbacks {
   }
 
   @override
+  void broadcastWatchEvent(WatchEvent event) {
+    watchEvents.add(event);
+  }
+
+  @override
   void computingPackageMap(bool computing) {
     // Do nothing.
   }