Add a command-line option about status email in the layout test analyzer.

media/tools/layout_tests/layouttest_analyzer_helpers.py

 #!/usr/bin/python
 # Copyright (c) 2011 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.
 
 """Helper functions for the layout test analyzer."""
 
 from datetime import datetime
 from email.mime.multipart import MIMEMultipart
 from email.mime.text import MIMEText
@@ skipping 246 matching lines @@
         if 'Bugs' in te_info:
           for bug in te_info['Bugs']:
             if bug not in bug_map:
               bug_map[bug] = []
             bug_map[bug].append((name, main_te_info))
     return bug_map
 
 
 def SendStatusEmail(prev_time, analyzer_result_map, prev_analyzer_result_map,
                     bug_anno_map, receiver_email_address, test_group_name,
-                    appended_text_to_email):
+                    appended_text_to_email, email_only_change_mode):
   """Send status email.
 
   Args:
     prev_time: the date string such as '2011-10-09-11'. This format has been
         used in this analyzer.
     analyzer_result_map: current analyzer result.
     prev_analyzer_result_map: previous analyzer result, which is read from
         a file.
     bug_anno_map: bug annotation map where bug name and annotations are
         stored.
     receiver_email_address: receiver's email address.
     test_group_name: string representing the test group name (e.g., 'media').
     appended_text_to_email: a text which is appended at the end of the status
         email.
+    email_only_change_mode: when this is true, the analyzer sends out the
+        status email only when there is change in the analyzer result compared
+        to the last result. When this is false, it sends the email out every
+        time it runs.
   """
   diff_map = analyzer_result_map.CompareToOtherResultMap(
       prev_analyzer_result_map)
+  # Do not email when |email_only_change_mode| is true and there is no change
+  # in the result compared to the last result.
+  if (email_only_change_mode and not any(diff_map['whole']) and
+      not any(diff_map['skip']) and not any(diff_map['nonskip'])):
+    return
   output_str = analyzer_result_map.ConvertToString(prev_time,
                                                    diff_map, bug_anno_map)
   # Add diff info about skipped/non-skipped test.
   prev_time = datetime.strptime(prev_time, '%Y-%m-%d-%H')
   prev_time = time.mktime(prev_time.timetuple())
   testname_map = {}
   for test_group in ['skip', 'nonskip']:
     for i in range(2):
       for (k, _) in diff_map[test_group][i]:
         testname_map[k] = True
@@ skipping 148 matching lines @@
           list2 = map2[name]['te_info']
           te_diff = [item for item in list1 if not item in list2]
           if te_diff:
               name_list.append((name, te_diff))
       else:
         name_list.append((name, value1))
     return name_list
 
   return (GetDiffBetweenMapsHelper(map1, map2, lookIntoTestExpectationInfo),
           GetDiffBetweenMapsHelper(map2, map1, lookIntoTestExpectationInfo))