Implement search for local elements.

pkg/analyzer/lib/src/summary/index_unit.dart

Index: pkg/analyzer/lib/src/summary/index_unit.dart
diff --git a/pkg/analyzer/lib/src/summary/index_unit.dart b/pkg/analyzer/lib/src/summary/index_unit.dart
index 19028b9f2bb78e31aa067524eddb0de20d691490..4dcb9808cb2935a85914de8c3ac96183d1cb213d 100644
--- a/pkg/analyzer/lib/src/summary/index_unit.dart
+++ b/pkg/analyzer/lib/src/summary/index_unit.dart
@@ -517,6 +517,10 @@ class _IndexContributor extends GeneralizingAstVisitor {
           element.field, IndexRelationKind.IS_REFERENCED_BY, node, true);
       return;
     }
+    // ignore a local reference to a parameter
+    if (element is ParameterElement && node.parent is! Label) {
+      return;
+    }
     // record specific relations
     recordRelation(
         element, IndexRelationKind.IS_REFERENCED_BY, node, isQualified);