Add SourceRange support to navigation collector

pkg/analyzer_plugin/lib/utilities/navigation/navigation.dart

Index: pkg/analyzer_plugin/lib/utilities/navigation/navigation.dart
diff --git a/pkg/analyzer_plugin/lib/utilities/navigation/navigation.dart b/pkg/analyzer_plugin/lib/utilities/navigation/navigation.dart
index 7205cc6654acf24e48e8aa6b588dcc8e373c76fe..462448b29ccc9723fe6ead666ed5d822cb704ccf 100644
--- a/pkg/analyzer_plugin/lib/utilities/navigation/navigation.dart
+++ b/pkg/analyzer_plugin/lib/utilities/navigation/navigation.dart
@@ -4,6 +4,7 @@
 
 import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/file_system/file_system.dart';
+import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer_plugin/protocol/protocol.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart'
     show ElementKind, Location;
@@ -32,6 +33,13 @@ abstract class DartNavigationRequest implements NavigationRequest {
  */
 abstract class NavigationCollector {
   /**
+   * Record a new navigation region corresponding to the given [range] that
+   * should navigate to the given [targetLocation].
+   */
+  void addRange(
+      SourceRange range, ElementKind targetKind, Location targetLocation);
+
+  /**
    * Record a new navigation region with the given [offset] and [length] that
    * should navigate to the given [targetLocation].
    */