Make the externally connectable browser test clobber all of the builtins,

chrome/renderer/resources/extensions/searchbox_api.js

 // Copyright 2012 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.
 
 var chrome;
 if (!chrome)
   chrome = {};
 
 if (!chrome.embeddedSearch) {
   chrome.embeddedSearch = new function() {
@@ skipping 82 matching lines @@
             var newRelevance = result.rankingData.relevance;
             if (newRelevance > oldRelevance) {
               urlToResultMap[url] = result;
             }
           } else {
             urlToResultMap[url] = result;
           }
         }
         var dedupedResults = [];
         for (url in urlToResultMap) {
-          dedupedResults.push(urlToResultMap[url]);
+          $Array.push(dedupedResults, urlToResultMap[url]);
         }
         return dedupedResults;
       }
 
       var lastPrefixQueriedForDuplicates = '';
       var numDedupeAttempts = 0;
 
       function DedupeClientSuggestions(clientSuggestions) {
         var userInput = GetQuery();
         if (userInput == lastPrefixQueriedForDuplicates) {
@@ skipping 182 matching lines @@
       this.onthemechange = null;
       this.oninputstart = null;
       this.oninputcancel = null;
     };
 
     // Export legacy searchbox API.
     // TODO: Remove this when Instant Extended is fully launched.
     chrome.searchBox = this.searchBox;
   };
 }