[Telemetry] Ensure that story display names are unique

telemetry/telemetry/story/story.py

 # Copyright 2015 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 re
 
 from telemetry.story import shared_state as shared_state_module
 
 _next_story_id = 0
 
@@ skipping 68 matching lines @@
     return self._id
 
   @property
   def name(self):
     return self._name
 
   @property
   def grouping_keys(self):
     return self._grouping_keys
 
+  @property
+  def display_name_and_grouping_key_tuple(self):
+    return self.display_name, tuple(self.grouping_keys.iteritems())
 
   def AsDict(self):
     """Converts a story object to a dict suitable for JSON output."""
     d = {
       'id': self._id,
     }
     if self._name:
       d['name'] = self._name
     return d
 
@@ skipping 24 matching lines @@
   def serving_dir(self):
     """Returns the absolute path to a directory with hash files to data that
        should be updated from cloud storage, or None if no files need to be
        updated.
     """
     return None
 
   @property
   def make_javascript_deterministic(self):
     return self._make_javascript_deterministic