Plumb IterationInfo from telemetry to a diagnostic

telemetry/telemetry/internal/story_runner_unittest.py

Index: telemetry/telemetry/internal/story_runner_unittest.py
diff --git a/telemetry/telemetry/internal/story_runner_unittest.py b/telemetry/telemetry/internal/story_runner_unittest.py
index da326424501b435e2a5b35240e6489bd6c1deaae..e15538cac714b691258244d4d0f1d4974cb18fb7 100644
--- a/telemetry/telemetry/internal/story_runner_unittest.py
+++ b/telemetry/telemetry/internal/story_runner_unittest.py
@@ -111,6 +111,11 @@ class DummyLocalStory(story_module.Story):
   def is_local(self):
     return True
 
+  @property
+  def url(self):
+    return 'data:,'
+
+
 class MixedStateStorySet(story_module.StorySet):
   @property
   def allow_mixed_story_states(self):
@@ -689,6 +694,10 @@ class StoryRunnerTest(unittest.TestCase):
         self.was_run = True
         raise legacy_page_test.Failure
 
+      @property
+      def url(self):
+        return 'data:,'
+
     self.SuppressExceptionFormatting()
 
     story_set = story_module.StorySet()