[Findit] Pass changed files info to Fracas, 2 face design.

appengine/findit/crash/scorers/scorer.py

 # Copyright 2016 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.
 
 """Interface of scorers to score and reason Result.
 
 A Scorer represents a heuristic rule to score a culprit cl result.
 """
 
 import logging
 
 
 class Scorer(object):  # pragma: no cover.
 
   def GetMetric(self, result):
     raise NotImplementedError()
 
   def Score(self, metric):
-    """Score the result based on extracted metric."""
+    """Scores the result based on extracted metric."""
     raise NotImplementedError()
 
   def Reason(self, metric, score):
-    """Given the reason of this score."""
+    """Gives the reason of this score."""
+    raise NotImplementedError()
+
+  def ChangedFiles(self, result):
+    """Returns the changed files info dict."""
     raise NotImplementedError()
 
   def __call__(self, result):
     """Returns score and reason of this result."""
     metric = self.GetMetric(result)
     if metric is None:
       logging.warning('Cannot get needed metric of result %s for scorer %s',
                       repr(result.ToDict()), self.name)
       return 0, ''
 
     score = self.Score(metric)
     reason = self.Reason(metric, score)
-    return score, reason
+    changed_files = self.ChangedFiles(result)
+    return score, reason, changed_files
 
   @property
   def name(self):
     return self.__class__.__name__