Lazy load chrome.* APIs

chrome/renderer/resources/extensions/bluetooth_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 Bluetooth API.
+// Custom binding for the Bluetooth API.
+
+var binding = require('binding').Binding.create('bluetooth');
 
 var chromeHidden = requireNative('chrome_hidden').GetChromeHidden();
+var chrome = requireNative('chrome').GetChrome();
 var sendRequest = require('sendRequest').sendRequest;
 var lastError = require('lastError');
 
-// Use custom bindings to create an undocumented event listener that will
+// Use custom binding to create an undocumented event listener that will
 // receive events about device discovery and call the event listener that was
 // provided with the request to begin discovery.
-chromeHidden.registerCustomHook('bluetooth', function(api) {
+binding.registerCustomHook(function(api) {
   var apiFunctions = api.apiFunctions;
 
   chromeHidden.bluetooth = {};
 
-  function callCallbackIfPresent(args) {
-    if (typeof(args[args.length-1]) == "function") {
-      args[args.length-1]();
-    }
+  function callCallbackIfPresent(args, error) {
+    var callback = args[args.length - 1];
+    if (typeof(callback) == "function")
+      lastError.run(error, callback);
   }
 
   chromeHidden.bluetooth.deviceDiscoveredHandler = null;
   chromeHidden.bluetooth.onDeviceDiscovered =
       new chrome.Event("bluetooth.onDeviceDiscovered");
   function clearDeviceDiscoveredHandler() {
     chromeHidden.bluetooth.onDeviceDiscovered.removeListener(
         chromeHidden.bluetooth.deviceDiscoveredHandler);
     chromeHidden.bluetooth.deviceDiscoveredHandler = null;
   }
   apiFunctions.setHandleRequest('startDiscovery',
       function() {
         var args = arguments;
         if (args.length > 0 && args[0] && args[0].deviceCallback) {
           if (chromeHidden.bluetooth.deviceDiscoveredHandler != null) {
-            lastError.set("Concurrent discovery is not allowed.");
-            callCallbackIfPresent(args);
+            callCallbackIfPresent(args, "Concurrent discovery is not allowed.");
             return;
           }
 
           chromeHidden.bluetooth.deviceDiscoveredHandler =
               args[0].deviceCallback;
           chromeHidden.bluetooth.onDeviceDiscovered.addListener(
               chromeHidden.bluetooth.deviceDiscoveredHandler);
           sendRequest(this.name,
                       args,
                       this.definition.parameters,
                       {customCallback:this.customCallback});
         } else {
-          lastError.set("deviceCallback is required in the options object");
-          callCallbackIfPresent(args);
+          callCallbackIfPresent(
+              args, "deviceCallback is required in the options object");
+          return;
         }
       });
   apiFunctions.setCustomCallback('startDiscovery',
       function(name, request, response) {
         if (chrome.runtime.lastError) {
           clearDeviceDiscoveredHandler();
           return;
         }
       });
   apiFunctions.setHandleRequest('stopDiscovery',
@@ skipping 83 matching lines @@
           throw new Error("getDevices must be passed options with a " +
               "deviceCallback.");
         }
 
         chromeHidden.bluetooth.getDevicesState = state;
         addDeviceSearchListeners();
 
         return args;
       });
 });
+
+exports.binding = binding.generate();