extract LocalLibraryContributor from imported reference contributor

pkg/analysis_server/lib/src/provisional/completion/dart/completion_plugin.dart

Index: pkg/analysis_server/lib/src/provisional/completion/dart/completion_plugin.dart
diff --git a/pkg/analysis_server/lib/src/provisional/completion/dart/completion_plugin.dart b/pkg/analysis_server/lib/src/provisional/completion/dart/completion_plugin.dart
index cb3a33b469c3d72d6f23957ee6ba0089ec46965b..805d8377ffbfb8094748db13ea9f806a6ee28b83 100644
--- a/pkg/analysis_server/lib/src/provisional/completion/dart/completion_plugin.dart
+++ b/pkg/analysis_server/lib/src/provisional/completion/dart/completion_plugin.dart
@@ -16,6 +16,7 @@ import 'package:analysis_server/src/services/completion/dart/label_contributor.d
 import 'package:analysis_server/src/services/completion/dart/library_member_contributor.dart';
 import 'package:analysis_server/src/services/completion/dart/library_prefix_contributor.dart';
 import 'package:analysis_server/src/services/completion/dart/local_constructor_contributor.dart';
+import 'package:analysis_server/src/services/completion/dart/local_library_contributor.dart';
 import 'package:analysis_server/src/services/completion/dart/local_reference_contributor.dart';
 import 'package:analysis_server/src/services/completion/dart/named_constructor_contributor.dart';
 import 'package:analysis_server/src/services/completion/dart/static_member_contributor.dart';
@@ -93,6 +94,8 @@ class DartCompletionPlugin implements Plugin {
     registerExtension(DART_COMPLETION_CONTRIBUTOR_EXTENSION_POINT_ID,
         () => new LocalConstructorContributor());
     registerExtension(DART_COMPLETION_CONTRIBUTOR_EXTENSION_POINT_ID,
+        () => new LocalLibraryContributor());
+    registerExtension(DART_COMPLETION_CONTRIBUTOR_EXTENSION_POINT_ID,
         () => new LocalReferenceContributor());
     registerExtension(DART_COMPLETION_CONTRIBUTOR_EXTENSION_POINT_ID,
         () => new NamedConstructorContributor());