Mocha adapter for Polymer browser tests.

A custom reporter enables mocha in WebUI browser tests. This is
used by a new BrowserTest base class, PolymerTest, to configure
mocha.

Relevant browser_tests sample output: http://pastebin.com/raw.php?i=EeHrmtWH

BUG=482770

Review URL: https://codereview.chromium.org/1124873002

Cr-Commit-Position: refs/heads/master@{#332537}

1 files changed, 78 insertions, 0 deletions

diff --git a/chrome/test/data/webui/polymer_browser_test_base.js b/chrome/test/data/webui/polymer_browser_test_base.js
new file mode 100644
index 0000000..e628eda
--- /dev/null
+++ b/chrome/test/data/webui/polymer_browser_test_base.js
@@ -0,0 +1,78 @@
+// Copyright 2015 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 Framework for running JavaScript tests of Polymer elements.
+ */
+
+/**
+ * Test fixture for Polymer element testing.
+ * @constructor
+ * @extends testing.Test
+ */
+function PolymerTest() {
+}
+
+PolymerTest.prototype = {
+  __proto__: testing.Test.prototype,
+
+  /**
+   * Navigate to a WebUI to satisfy BrowserTest conditions. Override to load a
+   * more useful WebUI.
+   * @override
+   */
+  browsePreload: 'chrome://chrome-urls/',
+
+  /**
+   * The mocha adapter assumes all tests are async.
+   * @override
+   * @final
+   */
+  isAsync: true,
+
+  /**
+   * @override
+   * @final
+   */
+  extraLibraries: ['../../../../third_party/mocha/mocha.js',
+                   'mocha_adapter.js'],
+
+  /** @override */
+  setUp: function() {
+    testing.Test.prototype.setUp.call(this);
+
+    // Import Polymer before running tests.
+    suiteSetup(function(done) {
+      var link = document.createElement('link');
+      link.rel = 'import';
+      link.onload = function() {
+        done();
+      };
+      link.onerror = function() {
+        done(new Error('Failed to load Polymer!'));
+      };
+      link.href = 'chrome://resources/polymer/v0_8/polymer/polymer.html';
+      document.head.appendChild(link);
+    });
+  },
+};
+
+/**
+ * Imports the HTML file, then calls |done| on success or throws an error.
+ * @param {String} href The URL to load.
+ * @param {Function} done The done callback.
+ */
+PolymerTest.importHref = function(href, done) {
+  Polymer.Base.importHref(
+      href,
+      function() { done(); },
+      function() { throw new Error('Failed to load ' + href); });
+};
+
+/**
+ * Removes all content from the body.
+ */
+PolymerTest.clearBody = function() {
+  document.body.innerHTML = '';
+};