Fix ChromeVox next tests that passed without actually running.

chrome/browser/resources/chromeos/chromevox/testing/chromevox_next_e2e_test_base.js

Index: chrome/browser/resources/chromeos/chromevox/testing/chromevox_next_e2e_test_base.js
diff --git a/chrome/browser/resources/chromeos/chromevox/testing/chromevox_next_e2e_test_base.js b/chrome/browser/resources/chromeos/chromevox/testing/chromevox_next_e2e_test_base.js
index bf0f03babf9c89f1c2d514fbe24106be53e033ee..db99b8ca8518fabda2af5c0da61fe579f1e3f191 100644
--- a/chrome/browser/resources/chromeos/chromevox/testing/chromevox_next_e2e_test_base.js
+++ b/chrome/browser/resources/chromeos/chromevox/testing/chromevox_next_e2e_test_base.js
@@ -21,10 +21,15 @@ ChromeVoxNextE2ETest.prototype = {
   __proto__: ChromeVoxE2ETest.prototype,
 
   /**
-   * Launches a new tab with the given document, and runs callback when a load
-   * complete fires.
+   * Gets the desktop from the automation API and Launches a new tab with
+   * the given document, and runs |callback| when a load complete fires.
+   * Arranges to call |testDone()| after |callback| returns.
+   * NOTE: Callbacks creatd instide |opt_callback| must be wrapped with
+   * |this.newCallback| if passed to asynchonous calls.  Otherwise, the test
+   * will be finished prematurely.
    * @param {function() : void} doc Snippet wrapped inside of a function.
-   * @param {function()} opt_callback Called once the document is ready.
+   * @param {function(chrome.automation.AutomationNode)} callback
+   *     Called once the document is ready.
    */
   runWithLoadedTree: function(doc, callback) {
     callback = this.newCallback(callback);