Pass the sdk path to plugins

pkg/analysis_server/lib/src/analysis_server.dart

Index: pkg/analysis_server/lib/src/analysis_server.dart
diff --git a/pkg/analysis_server/lib/src/analysis_server.dart b/pkg/analysis_server/lib/src/analysis_server.dart
index 352c0029c707cf18b51ea8b7ea21bef767586fb3..0e7fe483173ca45d982a709bbe502d54df94933f 100644
--- a/pkg/analysis_server/lib/src/analysis_server.dart
+++ b/pkg/analysis_server/lib/src/analysis_server.dart
@@ -422,8 +422,12 @@ class AnalysisServer {
             new NotificationManager(channel, resourceProvider) {
     _performance = performanceDuringStartup;
 
-    pluginManager = new PluginManager(resourceProvider, _getByteStorePath(),
-        notificationManager, instrumentationService);
+    pluginManager = new PluginManager(
+        resourceProvider,
+        _getByteStorePath(),
+        sdkManager.defaultSdkDirectory,
+        notificationManager,
+        instrumentationService);
     PluginWatcher pluginWatcher =
         new PluginWatcher(resourceProvider, pluginManager);