Add more debugging code

pkg/analyzer/lib/src/dart/element/element.dart

 // Copyright (c) 2014, 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 analyzer.src.dart.element.element;
 
 import 'dart:collection';
 import 'dart:math' show min;
 
 import 'package:analyzer/dart/ast/ast.dart';
@@ skipping 1969 matching lines @@
   bool operator ==(Object object) {
     if (identical(this, object)) {
       return true;
     }
     return object is Element &&
         object.kind == kind &&
         object.location == location;
   }
 
   /**
+   * Append to the given [buffer] a comma-separated list of the names of the
+   * types of this element and every enclosing element.
+   */
+  void appendPathTo(StringBuffer buffer) {
+    Element element = this;
+    while (element != null) {
+      if (element != this) {
+        buffer.write(', ');
+      }
+      buffer.write(element.runtimeType);
+      String name = element.name;
+      if (name != null) {
+        buffer.write(' (');
+        buffer.write(name);
+        buffer.write(')');
+      }
+      element = element.enclosingElement;
+    }
+  }
+
+  /**
    * Append a textual representation of this element to the given [buffer].
    */
   void appendTo(StringBuffer buffer) {
     if (_name == null) {
       buffer.write("<unnamed ");
       buffer.write(runtimeType.toString());
       buffer.write(">");
     } else {
       buffer.write(_name);
     }
@@ skipping 2910 matching lines @@
 
   @override
   void visitElement(Element element) {
     int offset = element.nameOffset;
     if (offset != -1) {
       map[offset] = element;
     }
     super.visitElement(element);
   }
 }