[Telemetry] Add Expectation module that enables disabling benchmarks/stories

telemetry/telemetry/benchmark_unittest.py

 # Copyright 2014 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.
 
 import optparse
 import unittest
 
 from telemetry import android
 from telemetry import benchmark
 from telemetry.testing import options_for_unittests
@@ skipping 141 matching lines @@
       parser = optparse.OptionParser()
       benchmark.AddCommandLineArgs(parser)
       options.MergeDefaultValues(parser.get_default_values())
 
       b = PredicateBenchmark(page.Page(url='about:blank'))
       b.Run(options)
     finally:
       story_runner.Run = original_run_fn
 
     self.assertTrue(validPredicate[0])
+
+  def testBenchmarkExpectations(self):
+    b = TestBenchmark(story_module.Story(
+        shared_state_class=shared_page_state.SharedPageState))
+    expectations = b.GetExpectations()
+    self.assertTrue(
+        isinstance(
+            expectations, story_module.expectations.StoryExpectations))