Get the highlights test to work with the new driver

pkg/analysis_server/test/analysis/notification_highlights_test.dart

Index: pkg/analysis_server/test/analysis/notification_highlights_test.dart
diff --git a/pkg/analysis_server/test/analysis/notification_highlights_test.dart b/pkg/analysis_server/test/analysis/notification_highlights_test.dart
index 714ab6ba0b20943b01d224dc56f3613efd5e62be..98f5d57220eab0849193ef376cfdd063d5d68389 100644
--- a/pkg/analysis_server/test/analysis/notification_highlights_test.dart
+++ b/pkg/analysis_server/test/analysis/notification_highlights_test.dart
@@ -23,9 +23,7 @@ main() {
 @reflectiveTest
 class AnalysisNotificationHighlightsTest extends AbstractAnalysisTest {
   List<HighlightRegion> regions;
-
-  @override
-  bool get enableNewAnalysisDriver => false;
+  Completer _regionsAvailable = new Completer();
 
   void assertHasRawRegion(HighlightRegionType type, int offset, int length) {
     for (HighlightRegion region in regions) {
@@ -93,7 +91,14 @@ class AnalysisNotificationHighlightsTest extends AbstractAnalysisTest {
 
   Future prepareHighlights() {
     addAnalysisSubscription(AnalysisService.HIGHLIGHTS, testFile);
-    return waitForTasksFinished();
+    // The test would time out if the notification was not received soon enough,
+    // but the time-out is painfully long, so we provide a shorter timeout here.
+    new Future.delayed(new Duration(seconds: 2), () {
+      if (!_regionsAvailable.isCompleted) {
+        _regionsAvailable.complete(null);
+      }
+    });
+    return _regionsAvailable.future;
   }
 
   void processNotification(Notification notification) {
@@ -101,6 +106,7 @@ class AnalysisNotificationHighlightsTest extends AbstractAnalysisTest {
       var params = new AnalysisHighlightsParams.fromNotification(notification);
       if (params.file == testFile) {
         regions = params.regions;
+        _regionsAvailable.complete(null);
       }
     }
   }