Add support for sending a USB SET_CONFIGURATION request.

extensions/test/data/api_test/usb/transfer_failure/test.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.
 
 var usb = chrome.usb;
 
 function createErrorTest(resultCode, errorMessage) {
   return function() {
     usb.findDevices({vendorId: 0, productId: 0}, function(devices) {
       var device = devices[0];
       var transfer = new Object();
       transfer.direction = "out";
       transfer.endpoint = 1;
       transfer.data = new ArrayBuffer(0);
       usb.bulkTransfer(device, transfer, function (result) {
+        if (errorMessage) {
+          chrome.test.assertLastError(errorMessage);
+        } else {
+          chrome.test.assertNoLastError();
+        }
         chrome.test.assertTrue(resultCode == result.resultCode);
         chrome.test.succeed();
       });
     });
   };
 }
 
 var tests = [
   createErrorTest(0, undefined),
-  createErrorTest(1, "Transfer failed"),
-  createErrorTest(2, "Transfer timed out"),
+  createErrorTest(1, "Transfer failed."),
+  createErrorTest(2, "Transfer timed out."),
 ];
 
 chrome.test.runTests(tests);