[Predator] Pass flags to callstack detector and fix nit.

appengine/findit/crash/test/flag_manager_test.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 crash.flag_manager import ParsingFlag
 from crash.flag_manager import FlagManager
 from crash.test.stacktrace_test_suite import StacktraceTestSuite
 
 
 class ParsingFlagTest(StacktraceTestSuite):
@@ skipping 97 matching lines @@
     """Tests doing nothing if flag's condition is not met."""
     self.flag_manager.Register(
         'group',
         ParsingFlag('flag',
                     turn_on_condition=lambda line: 'flag marker' in line,
                     value=False))
     line = 'dummy line'
     self.flag_manager.ConditionallyTurnOnFlags(line)
     self.assertFalse(bool(self.flag_manager.Get('flag')))
 
+  def testDoNothingWhenThereIsNoCondition(self):
+    """Tests doing nothing if flag has empty condition."""
+    self.flag_manager.Register(
+        'group',
+        ParsingFlag('flag', value=False))
+    line = 'dummy line'
+    self.flag_manager.ConditionallyTurnOnFlags(line)
+    self.assertFalse(bool(self.flag_manager.Get('flag')))
+
   def testSettingFlag(self):
     """Tests using ``TurnOn`` and ``TurnOff`` to set flags."""
     self.flag_manager.Register('group', ParsingFlag('flag', value=False))
     self.flag_manager.TurnOn('flag')
     self.flag_manager.TurnOn('dummy_flag')
     self.assertTrue(self.flag_manager.Get('flag'))
     self.flag_manager.TurnOff('flag')
     self.flag_manager.TurnOff('dummy_flag')
     self.assertFalse(self.flag_manager.Get('flag'))