Cleanup interaction creation and add ExecuteJavaScript to action_runner.py

tools/perf/page_sets/gmail_compose_discard.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 GmailComposeDiscardPage(page_module.Page):
@@ skipping 11 matching lines @@
   def RunNavigateSteps(self, action_runner):
     action_runner.NavigateToPage(self)
     action_runner.RunAction(WaitAction(
       {
         'javascript': (
           'window.gmonkey !== undefined &&'
           'document.getElementById("gb") !== null')
       }))
 
   def ComposeClick(self, action_runner):
-    action_runner.RunAction(JavascriptAction({
-      'expression': '''
+    action_runner.ExecuteJavaScript('''
       var button=document.evaluate('//div[text()="COMPOSE"]',
-        document,null,XPathResult.FIRST_ORDERED_NODE_TYPE,null)
+          document,null,XPathResult.FIRST_ORDERED_NODE_TYPE,null)
           .singleNodeValue;
       var mousedownevent=new MouseEvent('mousedown',true,true,window,0,0,0,0,0,
         false,false,false,false,0,null);
       var mouseupevent=new MouseEvent('mouseup',true,true,window,0,0,0,0,0,
         false,false,false,false,0,null);
       button.dispatchEvent(mousedownevent);
-      button.dispatchEvent(mouseupevent);'''
-    }))
+      button.dispatchEvent(mouseupevent);''')
 
   def RunEndure(self, action_runner):
     action_runner.RunAction(WaitAction(
       {
         'xpath': '//div[text()="COMPOSE"]',
         'condition': 'element'
       }))
     self.ComposeClick(action_runner)
     action_runner.RunAction(WaitAction({"seconds": 1}))
     action_runner.RunAction(WaitAction(
@@ skipping 13 matching lines @@
   """
   Description: Gmail endure test: compose and discard an email.
   """
 
   def __init__(self):
     super(GmailComposeDiscardPageSet, self).__init__(
       credentials_path='data/credentials.json',
       user_agent_type='desktop')
 
     self.AddPage(GmailComposeDiscardPage(self))