NTP: Clean up of MetricsHandler class and namespacing chrome.send messages.

chrome/browser/resources/ntp4/logging.js

 // Copyright (c) 2011 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.
 
 /**
  * @fileOverview
  * Logging info for benchmarking purposes. Should be the first js file included.
  */
 
 /* Stack of events that has been logged. */
 var eventLog = [];
 
 /**
  * Logs an event.
  * @param {String} name The name of the event (can be any string).
  * @param {boolean} shouldLogTime If true, the event is used for benchmarking
  *     and the time is logged. Otherwise, just push the event on the event
  *     stack.
  */
 function logEvent(name, shouldLogTime) {
   if (shouldLogTime)
-    chrome.send('logEventTime', [name]);
+    chrome.send('metricsHandler:logEventTime', [name]);
   eventLog.push([name, Date.now()]);
 }
 
 logEvent('Tab.NewTabScriptStart', true);
 window.addEventListener('load', function(e) {
   logEvent('Tab.NewTabOnload', true);
 });
 document.addEventListener('DOMContentLoaded', function(e) {
   logEvent('Tab.NewTabDOMContentLoaded', true);
 });