Initial implementation of the kythe domain

pkg/analysis_server/lib/src/plugin/server_plugin.dart

Index: pkg/analysis_server/lib/src/plugin/server_plugin.dart
diff --git a/pkg/analysis_server/lib/src/plugin/server_plugin.dart b/pkg/analysis_server/lib/src/plugin/server_plugin.dart
index 741f4257b15014a378c9b54a7643a033f947e8cb..ed450ac6f6981ac61095678566c681db5ae382a7 100644
--- a/pkg/analysis_server/lib/src/plugin/server_plugin.dart
+++ b/pkg/analysis_server/lib/src/plugin/server_plugin.dart
@@ -19,6 +19,7 @@ import 'package:analysis_server/src/domain_analytics.dart';
 import 'package:analysis_server/src/domain_completion.dart';
 import 'package:analysis_server/src/domain_diagnostic.dart';
 import 'package:analysis_server/src/domain_execution.dart';
+import 'package:analysis_server/src/domain_kythe.dart';
 import 'package:analysis_server/src/domain_server.dart';
 import 'package:analysis_server/src/domains/analysis/navigation_dart.dart';
 import 'package:analysis_server/src/domains/analysis/occurrences_dart.dart';
@@ -309,6 +310,8 @@ class ServerPlugin implements Plugin {
         (AnalysisServer server) => new DiagnosticDomainHandler(server));
     registerExtension(domainId,
         (AnalysisServer server) => new AnalyticsDomainHandler(server));
+    registerExtension(
+        domainId, (AnalysisServer server) => new KytheDomainHandler(server));
 
     //
     // Register fix contributors.