Add Wait* API to ActionRunner to wrap over WaitAction.

tools/perf/page_sets/browser_control.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.
 # pylint: disable=W0401,W0614
 from telemetry.page.actions.all_page_actions import *
 from telemetry.page import page as page_module
 from telemetry.page import page_set as page_set_module
 
 
 class BrowserControlPage(page_module.Page):
   """ Why: Continually attach and detach a DOM tree from a basic document. """
 
   def __init__(self, page_set):
     super(BrowserControlPage, self).__init__(
       url='file://endure/browser_control.html',
       page_set=page_set,
       name='browser_control')
     self.user_agent_type = 'desktop'
 
   def RunEndure(self, action_runner):
-    action_runner.RunAction(WaitAction({'seconds': 2}))
+    action_runner.Wait(2)
 
 
 class BrowserControlPageSet(page_set_module.PageSet):
 
   """ Chrome Endure control test for the browser. """
 
   def __init__(self):
     super(BrowserControlPageSet, self).__init__(
       user_agent_type='desktop')
 
     self.AddPage(BrowserControlPage(self))