remove old completion API

pkg/analysis_server/lib/src/services/completion/dart/completion_manager.dart

Index: pkg/analysis_server/lib/src/services/completion/dart/completion_manager.dart
diff --git a/pkg/analysis_server/lib/src/services/completion/dart/completion_manager.dart b/pkg/analysis_server/lib/src/services/completion/dart/completion_manager.dart
index 2289a925a565f4a76a7af80fb835dbf6ae1f1a2f..cb9d813e72c863726269675ca33d081f3f4a750c 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart/completion_manager.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart/completion_manager.dart
@@ -88,17 +88,15 @@ class DartCompletionManager implements CompletionContributor {
 /**
  * The information about a requested list of completions within a Dart file.
  */
-class DartCompletionRequestImpl extends CompletionRequestImpl
-    implements DartCompletionRequest {
-  /**
-   * The [LibraryElement] representing dart:core
-   */
-  LibraryElement _coreLib;
+class DartCompletionRequestImpl implements DartCompletionRequest {
+  @override
+  final AnalysisContext context;
 
-  /**
-   * The [DartType] for Object in dart:core
-   */
-  InterfaceType _objectType;
+  @override
+  final Source source;
+
+  @override
+  final int offset;
 
   @override
   Expression dotTarget;
@@ -106,20 +104,35 @@ class DartCompletionRequestImpl extends CompletionRequestImpl
   @override
   Source librarySource;
 
-  OpType _opType;
+  @override
+  final ResourceProvider resourceProvider;
+
+  @override
+  final SearchEngine searchEngine;
 
   @override
   CompletionTarget target;
 
+  /**
+   * The [LibraryElement] representing dart:core
+   */
+  LibraryElement _coreLib;
+
+  /**
+   * The [DartType] for Object in dart:core
+   */
+  InterfaceType _objectType;
+
+  OpType _opType;
+
   DartCompletionRequestImpl._(
-      AnalysisContext context,
-      ResourceProvider resourceProvider,
-      SearchEngine searchEngine,
+      this.context,
+      this.resourceProvider,
+      this.searchEngine,
       this.librarySource,
-      Source source,
-      int offset,
-      CompilationUnit unit)
-      : super(context, resourceProvider, searchEngine, source, offset) {
+      this.source,
+      this.offset,
+      CompilationUnit unit) {
     _updateTargets(unit);
   }