Add frameId to executeScript/insertCSS

chrome/test/data/extensions/api_test/executescript/frame_id/script.js

 // Copyright (c) 2013 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.
 
 function getStyle(elem, name) {
   if (document.defaultView && document.defaultView.getComputedStyle) {
     name = name.toLowerCase();
 
     try {
       var s = document.defaultView.getComputedStyle(elem, '');
       return s && s.getPropertyValue(name);
     } catch (ex) {
       return null;
     }
   } else {
     return null;
   }
 }
 
 var bElement = document.getElementById('test2');
 var display = getStyle(bElement, 'display').toLowerCase();
 var extensionPort = chrome.runtime.connect();
 extensionPort.postMessage({message: display});