Added isError method to remoting.Xhr.Error to check for HTTP errors.

remoting/webapp/crd/js/xhr_unittest.js

 // Copyright 2014 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.
 
 /**
  * @fileoverview
  */
 
 (function() {
 
@@ skipping 163 matching lines @@
 
 //
 // The typical case.
 //
 
 QUnit.test('successful GET', function(assert) {
   var promise = new remoting.Xhr({
     method: 'GET',
     url: 'http://foo.com'
   }).start().then(function(response) {
+    assert.ok(!response.isError());
     assert.equal(response.status, 200);
     assert.equal(response.getText(), 'body');
   });
   assert.equal(fakeXhr.method, 'GET');
   assert.equal(fakeXhr.url, 'http://foo.com');
   assert.equal(fakeXhr.withCredentials, false);
   assert.equal(fakeXhr.requestBody, null);
   assert.ok(!('Content-type' in fakeXhr.requestHeaders));
   fakeXhr.respond(200, {}, 'body');
   return promise;
@@ skipping 141 matching lines @@
 });
 
 QUnit.test('GET with useIdentity', function(assert) {
   var xhr = new remoting.Xhr({
     method: 'GET',
     url: 'http://foo.com',
     useIdentity: true
   });
 
   xhr.start();
-
   var done = assert.async();
   fakeXhr.addEventListener('loadstart', function() {
     assert.equal(fakeXhr.requestHeaders['Authorization'],
                  'Bearer my_token');
     done();
   });
 });
 
+//
+// Error responses.
+//
+QUnit.test('GET with error response', function(assert) {
+  var promise = new remoting.Xhr({
+    method: 'GET',
+    url: 'http://foo.com'
+  }).start().then(function(response) {
+    assert.ok(response.isError());
+    assert.equal(response.status, 500);
+    assert.equal(response.getText(), 'body');
+  });
+  fakeXhr.respond(500, {}, 'body');
+  return promise;
+});
+
+QUnit.test('204 is not an error', function(assert) {
+  var promise = new remoting.Xhr({
+    method: 'GET',
+    url: 'http://foo.com'
+  }).start().then(function(response) {
+    assert.ok(!response.isError());
+    assert.equal(response.status, 204);
+    assert.equal(response.getText(), '');
+  });
+  fakeXhr.respond(204, {}, null);
+  return promise;
+});
+
+QUnit.test('GET with non-HTTP response', function(assert) {
+  var promise = new remoting.Xhr({
+    method: 'GET',
+    url: 'http://foo.com'
+  }).start().then(function(response) {
+    assert.ok(response.isError());
+  });
+  fakeXhr.respond(0, {}, null);
+  return promise;
+});
+
 })();