Add test suite for STS options page

After
https://chromium-review.googlesource.com/c/chromium/src/+/2613726
and
https://chromium-review.googlesource.com/c/chromium/src/+/2622754

there appears to be a lack of testing for Select to Speak's options page.

This change adds a basic sanity test and a foundation to write more as
features are added.

R=joelriley@google.com, katie@chromium.org

AX-Relnotes: n/a
Bug: none
Test: this.
Change-Id: Id9fc395b1b95c81fbea4e10bfc5fb86e3f3645fd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2626914
Commit-Queue: David Tseng <dtseng@chromium.org>
Reviewed-by: Katie Dektar <katie@chromium.org>
Cr-Commit-Position: refs/heads/master@{#843167}

chrome/browser/resources/chromeos/accessibility/common/testing/e2e_test_base.js

@@ -136,6 +136,33 @@ E2ETestBase = class extends testing.Test {
     });
   }
 
+  /**
+   * Opens the options page for the running extension and calls |callback| with
+   * the options page root once ready.
+   * @param {function(chrome.automation.AutomationNode)} callback
+   * @param {!RegExp} matchUrlRegExp The url pattern of the options page if
+   *     different than the supplied default pattern below.
+   */
+  runWithLoadedOptionsPage(callback, matchUrlRegExp = /options.html/) {
+    callback = this.newCallback(callback);
+    chrome.automation.getDesktop((desktop) => {
+      const listener = (event) => {
+        if (!matchUrlRegExp.test(event.target.docUrl) ||
+            !event.target.docLoaded) {
+          return;
+        }
+
+        desktop.removeEventListener(
+            chrome.automation.EventType.LOAD_COMPLETE, listener);
+
+        callback(event.target);
+      };
+      desktop.addEventListener(
+          chrome.automation.EventType.LOAD_COMPLETE, listener);
+      chrome.runtime.openOptionsPage();
+    });
+  }
+
   /**
    * Finds one specific node in the automation tree.
    * This function is expected to run within a callback passed to

chrome/browser/resources/chromeos/accessibility/select_to_speak/BUILD.gn

@@ -82,6 +82,7 @@ js2gtest("select_to_speak_extjs_tests") {
     "select_to_speak_keystroke_selection_test.js",
     "select_to_speak_mouse_selection_test.js",
     "select_to_speak_navigation_control_test.js",
+    "select_to_speak_options_test.js",
     "select_to_speak_prefs_test.js",
   ]
 

chrome/browser/resources/chromeos/accessibility/select_to_speak/select_to_speak_options_test.js

+// Copyright 2021 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.
+
+GEN_INCLUDE(['select_to_speak_e2e_test_base.js']);
+
+/**
+ * Browser tests for select-to-speak's options page.
+ */
+SelectToSpeakOptionsTest = class extends SelectToSpeakE2ETest {};
+
+TEST_F('SelectToSpeakOptionsTest', 'RendersContent', function() {
+  this.runWithLoadedOptionsPage(root => {
+    // Sanity check the page renders correctly by looking for an item close or
+    // at the very end of the page.
+    const enableNavControlsSwitch =
+        root.find({attributes: {name: 'Enable navigation controls'}});
+    assertNotNullNorUndefined(enableNavControlsSwitch);
+    assertEquals(
+        chrome.automation.RoleType.SWITCH, enableNavControlsSwitch.role);
+  });
+});