[system_health] Fix the lack of memory dump triggers on some user stories

Some system health stories have been overriding RunPageInteractions method directly
without implementing memory dump triggering.

This fixes those stories by changing them to override _DidLoadStory. It also add
tests to avoid mistakes like these in the future.

Review-Url: https://codereview.chromium.org/2924163005
Cr-Commit-Position: refs/heads/master@{#477949}

tools/perf/benchmarks/system_health_unittest.py

@@ -8,6 +8,7 @@ import unittest
 from benchmarks import system_health as system_health_benchmark
 from core import path_util
 from page_sets.system_health import system_health_stories
+from page_sets.system_health import system_health_story
 
 from telemetry import benchmark as benchmark_module
 from telemetry.core import discover
@@ -44,3 +45,21 @@ class TestSystemHealthBenchmarks(unittest.TestCase):
           b().CreateStorySet(None),
           system_health_stories.SystemHealthStorySet,
           '%r does not use SystemHealthStorySet' % b)
+
+
+class TestSystemHealthStories(unittest.TestCase):
+
+  def testNoOverrideRunPageInteractions(self):
+    desktop_stories = (
+        system_health_stories.DesktopSystemHealthStorySet().stories)
+    mobile_stories = (
+        system_health_stories.MobileSystemHealthStorySet().stories)
+    for s in desktop_stories + mobile_stories:
+      # Long running stories has their own way of collecting memory dumps,
+      # so they explicitly override RunPageInteractions method.
+      if s.name.startswith('long_running:'):
+        continue
+      self.assertEquals(s.__class__.RunPageInteractions,
+          system_health_story.SystemHealthStory.RunPageInteractions,
+          'Story %s overrides RunPageInteractions. Override _DidLoadDocument '
+          'instead' % s.name)

tools/perf/page_sets/system_health/media_stories.py

@@ -19,7 +19,7 @@ class _MediaStory(system_health_story.SystemHealthStory):
   STOP_SELECTOR = NotImplemented
   TIME_SELECTOR = NotImplemented
 
-  def RunPageInteractions(self, action_runner):
+  def _DidLoadDocument(self, action_runner):
     self._NavigateToMedia(action_runner)
     # Play Media.
     if self.PLAY_SELECTOR:

tools/perf/page_sets/system_health/multi_tab_stories.py

@@ -36,7 +36,7 @@ class MultiTabStory(system_health_story.SystemHealthStory):
         logging.warning('WaitForNetworkQuiescence() timeout, url[%d]: %s'
                         % (i, url))
 
-  def RunPageInteractions(self, action_runner):
+  def _DidLoadDocument(self, action_runner):
     for tab in action_runner.tab.browser.tabs:
       tab.Activate()
       tab.WaitForFrameToBeDisplayed()