Rename NavigationHolder to NavigationCollector.

pkg/analysis_server/lib/analysis/navigation/navigation_core.dart

Index: pkg/analysis_server/lib/analysis/navigation/navigation_core.dart
diff --git a/pkg/analysis_server/lib/analysis/navigation/navigation_core.dart b/pkg/analysis_server/lib/analysis/navigation/navigation_core.dart
index c708d9a85dc294f10afebbc4a782c80f7edf47e9..e8566f46b391445ea341f61ab4c96c2d1a4022fa 100644
--- a/pkg/analysis_server/lib/analysis/navigation/navigation_core.dart
+++ b/pkg/analysis_server/lib/analysis/navigation/navigation_core.dart
@@ -17,10 +17,10 @@ import 'package:analyzer/src/generated/source.dart' show Source;
 abstract class NavigationContributor {
   /**
    * Contribute navigation regions for a part of the given [source] into the
-   * given [holder]. The part is specified by the [offset] and [length].
+   * given [collector]. The part is specified by the [offset] and [length].
    * The [context] can be used to get analysis results.
    */
-  void computeNavigation(NavigationHolder holder, AnalysisContext context,
+  void computeNavigation(NavigationCollector collector, AnalysisContext context,
       Source source, int offset, int length);
 }
 
@@ -30,7 +30,7 @@ abstract class NavigationContributor {
  *
  * Clients are not expected to subtype this class.
  */
-abstract class NavigationHolder {
+abstract class NavigationCollector {
   /**
    * Record a new navigation region with the given [offset] and [length] that
    * should navigation to the given [targetLocation].