<webview>: Implement declarativeWebRequest API

chrome/renderer/resources/extensions/webview_request_custom_bindings.js

+// Copyright (c) 2013 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 binding for the webViewRequest API.
+
+var binding = require('binding').Binding.create('webViewRequest');
+
+var declarativeWebRequestSchema =
+    requireNative('schema_registry').GetSchema('declarativeWebRequest');
+var utils = require('utils');
+var validate = require('schemaUtils').validate;
+
+binding.registerCustomHook(function(api) {
+  var webViewRequest = api.compiledApi;
+
+  // Returns the schema definition of type |typeId| defined in
+  // |declarativeWebRequestScheme.types|.
+  function getSchema(typeId) {
+    return utils.lookup(declarativeWebRequestSchema.types,
+                        'id',
+                        'declarativeWebRequest.' + typeId);
+  }
+
+  // Helper function for the constructor of concrete datatypes of the
+  // declarative webRequest API.
+  // Makes sure that |this| contains the union of parameters and
+  // {'instanceType': 'declarativeWebRequest.' + typeId} and validates the
+  // generated union dictionary against the schema for |typeId|.
+  function setupInstance(instance, parameters, typeId) {
+    for (var key in parameters) {
+      if ($Object.hasOwnProperty(parameters, key)) {
+        instance[key] = parameters[key];
+      }
+    }
+
+    instance.instanceType = 'declarativeWebRequest.' + typeId;
+    var schema = getSchema(typeId);
+    validate([instance], [schema]);
+  }
+
+  // Setup all data types for the declarative webRequest API from the schema.
+  for (var i = 0; i < declarativeWebRequestSchema.types.length; ++i) {
+    var typeSchema = declarativeWebRequestSchema.types[i];
+    var typeId = typeSchema.id.replace('declarativeWebRequest.', '');
+    var action = function(typeId) {
+      return function(parameters) {
+        setupInstance(this, parameters, typeId);
+      };
+    }(typeId);
+    webViewRequest[typeId] = action;
+  }
+});
+
+exports.binding = binding.generate();