Implement declarativeContent API.

chrome/renderer/resources/extensions/declarative_content_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 declarativeContent API.
+
+var chromeHidden = requireNative('chrome_hidden').GetChromeHidden();
+var utils = require('utils');
+var validate = require('schemaUtils').validate;
+
+chromeHidden.registerCustomHook('declarativeContent', function(api) {
+  // Returns the schema definition of type |typeId| defined in |namespace|.
+  function getSchema(namespace, typeId) {
+    var apiSchema = utils.lookup(api.apiDefinitions, 'namespace', namespace);
+    var resultSchema = utils.lookup(
+        apiSchema.types, 'id', namespace + '.' + typeId);
+    return resultSchema;
+  }
+
+  // Helper function for the constructor of concrete datatypes of the
+  // declarative content API.
+  // Makes sure that |this| contains the union of parameters and
+  // {'instanceType': 'declarativeContent.' + typeId} and validates the
+  // generated union dictionary against the schema for |typeId|.
+  function setupInstance(instance, parameters, typeId) {
+    for (var key in parameters) {
+      if (parameters.hasOwnProperty(key)) {
+        instance[key] = parameters[key];
+      }
+    }
+    instance.instanceType = 'declarativeContent.' + typeId;
+    var schema = getSchema('declarativeContent', typeId);
+    validate([instance], [schema]);
+  }
+
+  // Setup all data types for the declarative content API.
+  chrome.declarativeContent.PageStateMatcher = function(parameters) {
+    setupInstance(this, parameters, 'PageStateMatcher');
+  };
+  chrome.declarativeContent.ShowPageAction = function(parameters) {
+    setupInstance(this, parameters, 'ShowPageAction');
+  };
+});