[autotest] Factor out some result-gathering code

In preparation for some reworking of the way we reimage devices,
factor out the code we use in the Suite class to wait for test results
so that we can re-use it in the Reimager class too.

BUG=chromium-os:22060
TEST=run_suite

Change-Id: I630d64e955c83dfd4e885f13a0500c62e30fe59c
Reviewed-on: https://gerrit.chromium.org/gerrit/26324
Tested-by: Chris Masone <cmasone@chromium.org>
Reviewed-by: Scott Zawalski <scottz@chromium.org>
Commit-Ready: Chris Masone <cmasone@chromium.org>
diff --git a/site_utils/run_suite.py b/site_utils/run_suite.py
index e844890..b408314 100755
--- a/site_utils/run_suite.py
+++ b/site_utils/run_suite.py
@@ -19,6 +19,7 @@
 import logging
 from autotest_lib.client.common_lib import global_config
 from autotest_lib.server.cros import dynamic_suite, frontend_wrappers
+from autotest_lib.server.cros import job_status
 from autotest_lib.client.common_lib import logging_config, logging_manager
 
 CONFIG = global_config.global_config
@@ -151,9 +152,9 @@
         @param entry: an entry dict, as returned by get_details_test_views().
         """
         start_candidate = datetime.datetime.strptime(entry['test_started_time'],
-                                                     dynamic_suite.TIME_FMT)
+                                                     job_status.TIME_FMT)
         end_candidate = datetime.datetime.strptime(entry['test_finished_time'],
-                                                   dynamic_suite.TIME_FMT)
+                                                   job_status.TIME_FMT)
         if entry['test_name'] == 'SERVER_JOB':
             self.suite_start_time = start_candidate
         elif entry['test_name'] == 'try_new_image':