Applied changes from emailed code review

lib/rules.js

 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 Cu.import("resource://gre/modules/Services.jsm");
 Cu.import("resource://gre/modules/FileUtils.jsm");
 
 let {Prefs} = require("prefs");
 
 let RULES_VERSION = 2;
@@ skipping 132 matching lines @@
   let customRules = Prefs.custom_replace;
   for (let searchString in customRules)
   {
     let replacement = customRules[searchString];
     searchString = searchString.toLowerCase();
     if (/^re:+/.test(searchString))
       domain = domain.replace(new RegExp(RegExp.rightContext, "g"), replacement);
     else
       domain = domain.replace(searchString, replacement);
   }
+  
+  // Apply user's whitelist
+  let whitelist = Prefs.whitelist;
+  if (whitelist.hasOwnProperty(domain) || /^www\./.test(domain) && whitelist.hasOwnProperty(domain.substr(4)))
+  {
+    return domain;
+  }
 
   // Now apply our rules on the domain name
   for (let i = 0, l = rules.expressions.length; i < l; i++)
     domain = applyExpression(domain, rules.expressions[i]);
 
   // Find similar known domains, test domains without the www. prefix
   if (domain.substr(0, 4) == "www.")
     domain = "www." + getBestMatch(domain.substr(4), rules.domain, 1, ".");
   else
     domain = getBestMatch(domain, rules.domain, 1, ".");
@@ skipping 142 matching lines @@
       bestSuggestionDistance = distance;
       bestSuggestionMatched = matchedLen;
       bestSuggestionPriority = priority;
     }
   }
   if (bestSuggestion)
     return input.substr(0, input.length - bestSuggestionMatched) + bestSuggestion;
   else
     return input;
 }