[Findit] Fix Key error in build_failure handler.

appengine/findit/handlers/result_status.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.
 
 from model import analysis_status
 
 # Additional status for swarming tasks and try jobs.
 NO_SWARMING_TASK_FOUND = 110
 NON_SWARMING_NO_RERUN = 120
-#Additional reasons for no try job information.
+# Additional reasons for no try job information.
 SWARMING_TASK_PENDING = 130
 SWARMING_TASK_RUNNING = 140
 SWARMING_TASK_ERROR = 150
 NO_FAILURE_RESULT_MAP = 160
 FLAKY = 200
+# Universal status for unknowns.
+UNKNOWN = 210
 
 NO_TRY_JOB_REASON_MAP = {
     NO_SWARMING_TASK_FOUND: NO_SWARMING_TASK_FOUND,
     NON_SWARMING_NO_RERUN: NON_SWARMING_NO_RERUN,
     NO_FAILURE_RESULT_MAP: NO_FAILURE_RESULT_MAP,
     analysis_status.PENDING: SWARMING_TASK_PENDING,
     analysis_status.RUNNING: SWARMING_TASK_RUNNING,
     analysis_status.ERROR: SWARMING_TASK_ERROR,
 }
 
 STATUS_MESSAGE_MAP = {
     analysis_status.PENDING: 'Try job is pending.',
     analysis_status.RUNNING: 'Try job is running.',
     analysis_status.COMPLETED: 'Not Found.',
     analysis_status.ERROR: 'Try job failed.',
     NO_SWARMING_TASK_FOUND: 'No swarming task found, hence no try job.',
     NON_SWARMING_NO_RERUN: ('No swarming task nor try job will be triggered'
                             ' for non-swarming steps.'),
     SWARMING_TASK_PENDING: 'Swarming task is pending, no try job yet.',
     SWARMING_TASK_RUNNING: 'Swarming task is running, no try job yet.',
     SWARMING_TASK_ERROR: (
         'Swarming task failed, try job will not be triggered.'),
     NO_FAILURE_RESULT_MAP: 'No swarming task nor try job was triggered.',
     FLAKY: 'Flaky tests.',
+    UNKNOWN: 'Unknown failure.'
 }