Extensions Docs Server: Generalize $ref's to work for any schema node

chrome/common/extensions/docs/server2/known_issues_data_source.py

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import csv
 import logging
 import operator
 from StringIO import StringIO
 
 import object_store
@@ skipping 24 matching lines @@
     for issue_dict in issues_reader:
       id = issue_dict.get('ID', '')
       title = issue_dict.get('Summary', '')
       if not id or not title:
         continue
       issues.append({ 'id': id, 'title': title })
     issues = sorted(issues, key=operator.itemgetter('title'))
     self._object_store.Set(url, issues, object_store.KNOWN_ISSUES)
     return issues
 
-  def __getitem__(self, key):
-    return self.get(key)
-
   def get(self, key):
     return {
       'open': self.GetIssues(OPEN_ISSUES_CSV_URL),
       'closed': self.GetIssues(CLOSED_ISSUES_CSV_URL)
     }.get(key, None)