Add second batch JS benchmark and code generator

tools/perf/page_sets/tough_scheduling_cases.py

Index: tools/perf/page_sets/tough_scheduling_cases.py
diff --git a/tools/perf/page_sets/tough_scheduling_cases.py b/tools/perf/page_sets/tough_scheduling_cases.py
index 00fcb6eef492d92c42fd8f4ce2afb8502e7a42e0..9d8d5f72749d861442feede26e17188282386c2a 100644
--- a/tools/perf/page_sets/tough_scheduling_cases.py
+++ b/tools/perf/page_sets/tough_scheduling_cases.py
@@ -369,6 +369,36 @@ class SynchronizedScrollOffsetPage(ToughSchedulingCasesPage):
     interaction.End()
 
 
+class SecondBatchJsPage(ToughSchedulingCasesPage):
+
+  """Why: For testing dynamically loading a large batch of Javascript and
+          running a part of it in response to user input.
+  """
+
+  def __init__(self, page_set, variant='medium'):
+    super(SecondBatchJsPage, self).__init__(
+        url='file://tough_scheduling_cases/second_batch_js.html?%s' % variant,
+        page_set=page_set)
+
+  def RunPageInteractions(self, action_runner):
+    # Do a dummy tap to warm up the synthetic tap code path.
+    action_runner.TapElement(selector='div[id="spinner"]')
+    # Begin the action immediately because we want the page to update smoothly
+    # even while resources are being loaded.
+    action_runner.WaitForJavaScriptCondition('window.__ready !== undefined')
+
+    interaction = action_runner.BeginGestureInteraction(
+        'LoadAction', is_smooth=True)
+    action_runner.ClickElement(selector='input[id="load"]')
+    action_runner.WaitForJavaScriptCondition('window.__ready')
+    # Click one second after the resources have finished loading.
+    action_runner.Wait(1)
+    action_runner.TapElement(selector='input[id="run"]')
+    # Wait a little bit for things to settle.
+    action_runner.Wait(.3)

[rmcilroy, 2015/03/17 13:59:36]

Should we wait on the actual JS to finish here (or does action_runner.TapElement
do that implicitly)?

[Sami, 2015/03/18 14:05:32]

Right, good point. I'll make the test signal when it's done.

+    interaction.End()
+
+
 class ToughSchedulingCasesPageSet(page_set_module.PageSet):
 
   """Tough scheduler latency test cases."""
@@ -474,3 +504,7 @@ class ToughSchedulingCasesPageSet(page_set_module.PageSet):
         page_set=self))
       # Why: For measuring the latency of scroll-synchronized effects.

[rmcilroy, 2015/03/17 13:59:36]

optional nit - I know it's not your patch, but could you fix the indentation on
some of these comments? 

[Sami, 2015/03/18 14:05:32]

Yeah, those look pretty dire. Fixed.

     self.AddUserStory(SynchronizedScrollOffsetPage(page_set=self))
+    # Why: Test loading a large amount of Javascript.
+    self.AddUserStory(SecondBatchJsPage(page_set=self, variant='light'))
+    self.AddUserStory(SecondBatchJsPage(page_set=self, variant='medium'))
+    self.AddUserStory(SecondBatchJsPage(page_set=self, variant='heavy'))