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

chrome/renderer/resources/extensions/web_request_internal_custom_bindings.js

Index: chrome/renderer/resources/extensions/web_request_internal_custom_bindings.js
diff --git a/chrome/renderer/resources/extensions/web_request_internal_custom_bindings.js b/chrome/renderer/resources/extensions/web_request_internal_custom_bindings.js
index 45ebec2df98527a1fd6b8eb6a1b99a0cc3acf59e..7d168050da79485dd6797137b6d69b9d9210cd2e 100644
--- a/chrome/renderer/resources/extensions/web_request_internal_custom_bindings.js
+++ b/chrome/renderer/resources/extensions/web_request_internal_custom_bindings.js
@@ -67,7 +67,7 @@ WebRequestEvent.prototype.addListener =
   var subEventName = webRequestNatives.GetUniqueSubEventName(this.eventName_);
   // Note: this could fail to validate, in which case we would not add the
   // subEvent listener.
-  validate(Array.prototype.slice.call(arguments, 1), this.extraArgSchemas_);
+  validate($Array.slice(arguments, 1), this.extraArgSchemas_);
   webRequestInternal.addEventListener(
       cb, opt_filter, opt_extraInfo, this.eventName_, subEventName,
       this.webViewInstanceId_);
@@ -79,7 +79,7 @@ WebRequestEvent.prototype.addListener =
     subEventCallback = function() {
       var requestId = arguments[0].requestId;
       try {
-        var result = cb.apply(null, arguments);
+        var result = $Function.apply(cb, null, arguments);
         webRequestInternal.eventHandled(
             eventName, subEventName, requestId, result);
       } catch (e) {
@@ -97,10 +97,10 @@ WebRequestEvent.prototype.addListener =
         webRequestInternal.eventHandled(
             eventName, subEventName, requestId, response);
       };
-      cb.apply(null, [details, handledCallback]);
+      $Function.apply(cb, null, [details, handledCallback]);
     };
   }
-  this.subEvents_.push(
+  $Array.push(this.subEvents_,
       {subEvent: subEvent, callback: cb, subEventCallback: subEventCallback});
   subEvent.addListener(subEventCallback);
 };
@@ -117,7 +117,7 @@ WebRequestEvent.prototype.removeListener = function(cb) {
       console.error(
           'Internal error: webRequest subEvent has orphaned listeners.');
     }
-    this.subEvents_.splice(idx, 1);
+    $Array.splice(this.subEvents_, idx, 1);
   }
 };
 
@@ -156,13 +156,13 @@ binding.registerCustomHook(function(api) {
   var apiFunctions = api.apiFunctions;
 
   apiFunctions.setHandleRequest('addEventListener', function() {
-    var args = Array.prototype.slice.call(arguments);
+    var args = $Array.slice(arguments);
     sendRequest(this.name, args, this.definition.parameters,
                 {forIOThread: true});
   });
 
   apiFunctions.setHandleRequest('eventHandled', function() {
-    var args = Array.prototype.slice.call(arguments);
+    var args = $Array.slice(arguments);
     sendRequest(this.name, args, this.definition.parameters,
                 {forIOThread: true});
   });