telemetry: Allow page tests to be configured via constructor

tools/telemetry/telemetry/benchmark.py

Index: tools/telemetry/telemetry/benchmark.py
diff --git a/tools/telemetry/telemetry/benchmark.py b/tools/telemetry/telemetry/benchmark.py
index bfdca6e76bed55a42554efd1242e0d496bfb12b5..065205dc174a1a212f9f5f590263fa0e2d2742ae 100644
--- a/tools/telemetry/telemetry/benchmark.py
+++ b/tools/telemetry/telemetry/benchmark.py
@@ -44,6 +44,15 @@ class Benchmark(command_line.Command):
   """
   options = {}
 
+  def __init__(self):
+    super(Benchmark, self).__init__()
+    self.page_test = self.CreatePageTest()
+    self.page_test.__name__ = self.__class__.__name__
+    if hasattr(self, '_disabled_strings'):
+      self.page_test._disabled_strings = self._disabled_strings
+    if hasattr(self, '_enabled_strings'):
+      self.page_test._enabled_strings = self._enabled_strings
+
   @classmethod
   def Name(cls):
     name = cls.__module__.split('.')[-1]
@@ -53,29 +62,26 @@ class Benchmark(command_line.Command):
       name += '.' + cls.page_set.Name()
     return name
 
-  @classmethod
-  def AddCommandLineArgs(cls, parser):
-    cls.PageTestClass().AddCommandLineArgs(parser)
+  def AddCommandLineArgs(self, parser):
+    self.page_test.AddCommandLineArgs(parser)
 
-    if hasattr(cls, 'AddTestCommandLineArgs'):
-      group = optparse.OptionGroup(parser, '%s test options' % cls.Name())
-      cls.AddTestCommandLineArgs(group)
+    if hasattr(self, 'AddTestCommandLineArgs'):
+      group = optparse.OptionGroup(parser, '%s test options' % self.Name())
+      self.AddTestCommandLineArgs(group)
       parser.add_option_group(group)
 
-  @classmethod
-  def SetArgumentDefaults(cls, parser):
-    cls.PageTestClass().SetArgumentDefaults(parser)
+  def SetArgumentDefaults(self, parser):
+    self.page_test.SetArgumentDefaults(parser)
     default_values = parser.get_default_values()
     invalid_options = [
-        o for o in cls.options if not hasattr(default_values, o)]
+        o for o in self.options if not hasattr(default_values, o)]
     if invalid_options:
       raise InvalidOptionsError('Invalid benchmark options: %s',
                                 ', '.join(invalid_options))
-    parser.set_defaults(**cls.options)
+    parser.set_defaults(**self.options)
 
-  @classmethod
-  def ProcessCommandLineArgs(cls, parser, args):
-    cls.PageTestClass().ProcessCommandLineArgs(parser, args)
+  def ProcessCommandLineArgs(self, parser, args):
+    self.page_test.ProcessCommandLineArgs(parser, args)
 
   def CustomizeBrowserOptions(self, options):
     """Add browser options that are required by this benchmark."""
@@ -87,14 +93,6 @@ class Benchmark(command_line.Command):
     """Run this test with the given options."""
     self.CustomizeBrowserOptions(finder_options.browser_options)
 
-    pt = self.PageTestClass()()
-    pt.__name__ = self.__class__.__name__
-
-    if hasattr(self, '_disabled_strings'):
-      pt._disabled_strings = self._disabled_strings
-    if hasattr(self, '_enabled_strings'):
-      pt._enabled_strings = self._enabled_strings
-
     expectations = self.CreateExpectations()
     us = self.CreateUserStorySet(finder_options)
 
@@ -103,7 +101,8 @@ class Benchmark(command_line.Command):
     benchmark_metadata = self.GetMetadata()
     results = results_options.CreateResults(benchmark_metadata, finder_options)
     try:
-      page_runner.Run(pt, us, expectations, finder_options, results)
+      page_runner.Run(self.page_test, us, expectations,
+                      finder_options, results)
     except page_test.TestNotSupportedOnPlatformFailure as failure:
       logging.warning(str(failure))
 
@@ -173,17 +172,16 @@ class Benchmark(command_line.Command):
         extracted_profile_dir_path)
     options.browser_options.profile_dir = extracted_profile_dir_path
 
-  @classmethod
-  def PageTestClass(cls):
+  def CreatePageTest(self):
     """Get the PageTest for this Benchmark.
 
     If the Benchmark has no PageTest, raises NotImplementedError.
     """
-    if not hasattr(cls, 'test'):
+    if not hasattr(self, 'test'):
       raise NotImplementedError('This test has no "test" attribute.')
-    if not issubclass(cls.test, page_test.PageTest):
-      raise TypeError('"%s" is not a PageTest.' % cls.test.__name__)
-    return cls.test
+    if not issubclass(self.test, page_test.PageTest):
+      raise TypeError('"%s" is not a PageTest.' % self.test.__name__)
+    return self.test()
 
   def CreatePageSet(self, options):  # pylint: disable=W0613
     """Get the page set this test will run on.