Turn on the new task model by default in analysis server.

pkg/analysis_server/test/integration/integration_tests.dart

Index: pkg/analysis_server/test/integration/integration_tests.dart
diff --git a/pkg/analysis_server/test/integration/integration_tests.dart b/pkg/analysis_server/test/integration/integration_tests.dart
index 8278e263e9edabea083d7d86bc387a9e7298b106..6e7273e2a93ff028c61c3709c296d386c4ccd1fb 100644
--- a/pkg/analysis_server/test/integration/integration_tests.dart
+++ b/pkg/analysis_server/test/integration/integration_tests.dart
@@ -597,7 +597,7 @@ class Server {
       {bool debugServer: false,
       int diagnosticPort,
       bool profileServer: false,
-      bool newTaskModel: false,
+      bool newTaskModel: true,
       bool useAnalysisHighlight2: false}) {
     if (_process != null) {
       throw new Exception('Process already started');
@@ -627,8 +627,8 @@ class Server {
     if (useAnalysisHighlight2) {
       arguments.add('--useAnalysisHighlight2');
     }
-    if (newTaskModel) {
-      arguments.add('--${analysisServer.Driver.ENABLE_NEW_TASK_MODEL}');
+    if (!newTaskModel) {
+      arguments.add('--${analysisServer.Driver.DISABLE_NEW_TASK_MODEL}');
     }
     print('Launching $serverPath');
     print('$dartBinary ${arguments.join(' ')}');