Revert of [Extensions] Finish freezing schema

extensions/renderer/resources/storage_area.js

 // Copyright 2014 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 normalizeArgumentsAndValidate =
     require('schemaUtils').normalizeArgumentsAndValidate
 var sendRequest = require('sendRequest').sendRequest;
 
 function extendSchema(schema) {
   var extendedSchema = $Array.slice(schema);
-  $Array.unshift(extendedSchema, {'type': 'string'});
+  extendedSchema.unshift({'type': 'string'});
   return extendedSchema;
 }
 
 function StorageArea(namespace, schema) {
   // Binds an API function for a namespace to its browser-side call, e.g.
   // storage.sync.get('foo') -> (binds to) ->
   // storage.get('sync', 'foo').
   //
   // TODO(kalman): Put as a method on CustombindingObject and re-use (or
   // even generate) for other APIs that need to do this. Same for other
   // callers of registerCustomType().
   var self = this;
   function bindApiFunction(functionName) {
     self[functionName] = function() {
       var funSchema = this.functionSchemas[functionName];
       var args = $Array.slice(arguments);
       args = normalizeArgumentsAndValidate(args, funSchema);
       return sendRequest(
           'storage.' + functionName,
           $Array.concat([namespace], args),
           extendSchema(funSchema.definition.parameters),
           {preserveNullInObjects: true});
     };
   }
   var apiFunctions = ['get', 'set', 'remove', 'clear', 'getBytesInUse'];
   $Array.forEach(apiFunctions, bindApiFunction);
 }
 
 exports.$set('StorageArea', StorageArea);