[Telemetry] Remove session_restore's use of PageTest.CanRunForPage.

tools/telemetry/telemetry/user_story/user_story_set_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 os
 import unittest
 
+from telemetry import user_story
+from telemetry.user_story import shared_user_story_state
 from telemetry.user_story import user_story_set
 from telemetry.util import cloud_storage
 
 
+# pylint: disable=abstract-method
+class SharedUserStoryStateBar(shared_user_story_state.SharedUserStoryState):
+  pass
+
+
+class UserStoryFoo(user_story.UserStory):
+  def __init__(self, name='', labels=None):
+    super(UserStoryFoo, self).__init__(
+        SharedUserStoryStateBar, name, labels)
+
+
 class UserStorySetFoo(user_story_set.UserStorySet):
   """ UserStorySetFoo is a user story created for testing purpose. """
   pass
 
 
 class UserStorySetTest(unittest.TestCase):
 
   def testUserStoryTestName(self):
     self.assertEquals('user_story_set_unittest', UserStorySetFoo.Name())
 
@@ skipping 17 matching lines @@
     self.assertEqual(public_uss.bucket, cloud_storage.PUBLIC_BUCKET)
 
     partner_uss = user_story_set.UserStorySet(
         cloud_storage_bucket=cloud_storage.PARTNER_BUCKET)
     self.assertEqual(partner_uss.bucket, cloud_storage.PARTNER_BUCKET)
 
     internal_uss = user_story_set.UserStorySet(
         cloud_storage_bucket=cloud_storage.INTERNAL_BUCKET)
     self.assertEqual(internal_uss.bucket, cloud_storage.INTERNAL_BUCKET)
 
-    self.assertRaises(ValueError, user_story_set.UserStorySet,
-                      cloud_storage_bucket='garbage_bucket')
+    with self.assertRaises(ValueError):
+      user_story_set.UserStorySet(cloud_storage_bucket='garbage_bucket')
+
+  def testRemoveWithEmptySetRaises(self):
+    uss = user_story_set.UserStorySet()
+    foo_story = UserStoryFoo()
+    with self.assertRaises(ValueError):
+      uss.RemoveUserStory(foo_story)
+
+  def testBasicAddRemove(self):
+    uss = user_story_set.UserStorySet()
+    foo_story = UserStoryFoo()
+    uss.AddUserStory(foo_story)
+    self.assertEqual([foo_story], uss.user_stories)
+
+    uss.RemoveUserStory(foo_story)
+    self.assertEqual([], uss.user_stories)