Issue 24599. Fix for requesting navigation for directives.

pkg/analysis_server/lib/src/domains/analysis/navigation_dart.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library domains.analysis.navigation_dart;
 
 import 'package:analysis_server/plugin/analysis/navigation/navigation_core.dart';
 import 'package:analysis_server/src/protocol_server.dart' as protocol;
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
@@ skipping 40 matching lines @@
   void _addRegion(int offset, int length, Element element) {
     if (element is FieldFormalParameterElement) {
       element = (element as FieldFormalParameterElement).field;
     }
     if (element == null || element == DynamicElementImpl.instance) {
       return;
     }
     if (element.location == null) {
       return;
     }
-    protocol.ElementKind kind =
-        protocol.convertElementKind(element.kind);
+    protocol.ElementKind kind = protocol.convertElementKind(element.kind);
     protocol.Location location = protocol.newLocation_fromElement(element);
     if (location == null) {
       return;
     }
     collector.addRegion(offset, length, kind, location);
   }
 
   void _addRegion_nodeStart_nodeEnd(AstNode a, AstNode b, Element element) {
     int offset = a.offset;
     int length = b.end - offset;
@@ skipping 246 matching lines @@
   visitNode(AstNode node) {
     // The node ends before the range starts.
     if (node.end < start) {
       return;
     }
     // The node starts after the range ends.
     if (node.offset > end) {
       return;
     }
     // The node starts or ends in the range.
-    if (isInRange(node.offset) || isInRange(node.end)) {
-      node.accept(visitor);
-      return;
+    if (node is! CompilationUnit) {
+      if (isInRange(node.offset) || isInRange(node.end) || node is Directive) {
+        node.accept(visitor);
+        return;
+      }
     }
     // Go deeper.
     super.visitNode(node);
   }
 }