[Findit] Moving check flake max_builds_to_look_back to config

appengine/findit/waterfall/test/waterfall_config_test.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.
 
 from waterfall import waterfall_config
 from waterfall.test import wf_testcase
 
 
 class MastersTest(wf_testcase.WaterfallTestCase):
 
@@ skipping 125 matching lines @@
         },
         waterfall_config.GetActionSettings())
 
   def testGetCheckFlakeSettings(self):
     self.assertEqual(
         {
             'lower_flake_threshold': 0.02,
             'upper_flake_threshold': 0.98,
             'max_flake_in_a_row': 4,
             'max_stable_in_a_row': 4,
-            'iterations_to_rerun': 100
+            'iterations_to_rerun': 100,
+            'max_build_numbers_to_look_back': 1000
         },
         waterfall_config.GetCheckFlakeSettings())