Sanitize inheritance in callers of utils.expose

extensions/renderer/resources/web_request_internal_custom_bindings.js

Index: extensions/renderer/resources/web_request_internal_custom_bindings.js
diff --git a/extensions/renderer/resources/web_request_internal_custom_bindings.js b/extensions/renderer/resources/web_request_internal_custom_bindings.js
index df10729e6b3fb66ebe2df2912d7ca9c127e1ca02..9d6975d8f3008c9d97ebe791e69e98ef95261b34 100644
--- a/extensions/renderer/resources/web_request_internal_custom_bindings.js
+++ b/extensions/renderer/resources/web_request_internal_custom_bindings.js
@@ -14,7 +14,7 @@ var idGeneratorNatives = requireNative('id_generator');
 var webRequestInternal;
 
 function GetUniqueSubEventName(eventName) {
-  return eventName + "/" + idGeneratorNatives.GetNextId();
+  return eventName + '/' + idGeneratorNatives.GetNextId();
 }
 
 // WebRequestEventImpl object. This is used for special webRequest events
@@ -44,6 +44,8 @@ function WebRequestEventImpl(eventName, opt_argSchemas, opt_extraArgSchemas,
                                 opt_webViewInstanceId);
   }
 }
+$Object.setPrototypeOf(WebRequestEventImpl, null);
+$Object.setPrototypeOf(WebRequestEventImpl.prototype, null);
 
 // Test if the given callback is registered for this event.
 WebRequestEventImpl.prototype.hasListener = function(cb) {