Improve web-app type safety.

remoting/webapp/me2mom/debug_log.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
  * Module to support logging debug messages.
  */
 
 'use strict';
 
 /** @suppress {duplicate} */
 var remoting = remoting || {};
 
-(function() {
-
-/** @constructor */
+/**
+ * @constructor
+ * @param {Element} logElement The HTML div to which to add log messages.
+ */
 remoting.DebugLog = function(logElement) {
   this.debugLog = logElement;
-}
+};
 
-// Maximum numer of lines to record in the debug log.
-// Only the most recent <n> lines are displayed.
-var MAX_DEBUG_LOG_SIZE = 1000;
+/** Maximum number of lines to record in the debug log. Only the most
+ *  recent <n> lines are displayed. */
+remoting.DebugLog.prototype.MAX_DEBUG_LOG_SIZE = 1000;
 
 /**
  * Add the given message to the debug log.
  *
  * @param {string} message The debug info to add to the log.
  */
 remoting.DebugLog.prototype.log = function(message) {
   // Remove lines from top if we've hit our max log size.
-  if (this.debugLog.childNodes.length == MAX_DEBUG_LOG_SIZE) {
+  if (this.debugLog.childNodes.length == this.MAX_DEBUG_LOG_SIZE) {
     this.debugLog.removeChild(this.debugLog.firstChild);
   }
 
   // Add the new <p> to the end of the debug log.
   var p = document.createElement('p');
   p.appendChild(document.createTextNode(message));
   this.debugLog.appendChild(p);
 
   // Scroll to bottom of div
   this.debugLog.scrollTop = this.debugLog.scrollHeight;
-}
+};
 
-}());
+/** @type {remoting.DebugLog} */
+remoting.debug = null;