Allow updateArgumentsPostValidate to support callbacks and added / removed arguments.

chrome/renderer/resources/extensions/storage_custom_bindings.js

 // Copyright (c) 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.
 
 // Custom bindings for the storage API.
 
 var chromeHidden = requireNative('chrome_hidden').GetChromeHidden();
+var normalizeArgumentsAndValidate =
+    require('schemaUtils').normalizeArgumentsAndValidate
 var sendRequest = require('sendRequest').sendRequest;
 
 chromeHidden.registerCustomType('storage.StorageArea', function() {
   function extendSchema(schema) {
     var extendedSchema = schema.slice();
     extendedSchema.unshift({'type': 'string'});
     return extendedSchema;

[not at google - send to devlin, 2012/06/07 03:15:04]

just curious, could you have used something like this black magic to solve your
problem in a different way?

(can't remember the specifics of your problem)

[benwells, 2012/06/07 04:11:48]

No I don't think this would help, not that I can see anyway.

   }
 
   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 CustomBindingsObject 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) {
-      this[functionName] = function() {
-        var schema = this.parameters[functionName];
-        chromeHidden.validate(arguments, schema);
+      self[functionName] = function() {
+        var funSchema = this.functionSchemas[functionName];

[not at google - send to devlin, 2012/06/07 03:15:04]

Woohoo!  Par-tay!

Ok I'll stop now.

+        var args = Array.prototype.slice.call(arguments);
+        args = normalizeArgumentsAndValidate(args, funSchema);
         return sendRequest(
             'storage.' + functionName,
-            [namespace].concat(Array.prototype.slice.call(arguments)),
-            extendSchema(schema));
+            [namespace].concat(args),
+            extendSchema(funSchema.definition.parameters));
       };
     }
     var apiFunctions = ['get', 'set', 'remove', 'clear', 'getBytesInUse'];
-    apiFunctions.forEach(bindApiFunction.bind(this));
+    apiFunctions.forEach(bindApiFunction);

[not at google - send to devlin, 2012/06/07 03:15:04]

thanks!

   }
 
   return StorageArea;
 });