Do not call doDefault for action verb select

In Blink, select (default action verb) often equates with 'click'.

A page author can quite reasonably have a node with role menuitem and add a click listener. In this instances, Blink gives us default action verb select.

ChromeVox calls do default and triggers undesirable side effects.

Bug: 889018
Test: manually on Gmail.
Change-Id: I774001aa355ecaa64dd45878f40828f63feecd1a
Reviewed-on: https://chromium-review.googlesource.com/1241843
Commit-Queue: David Tseng <dtseng@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#594036}

chrome/browser/resources/chromeos/chromevox/cvox2/background/background.js

@@ -432,11 +432,6 @@ Background.prototype = {
           AutomationPredicate.linkOrControl(node);
     };
 
-    // Always try to give nodes selection.
-    if (start.defaultActionVerb == chrome.automation.DefaultActionVerb.SELECT) {
-      start.doDefault();
-    }
-
     // Next, try to focus the start or end node.
     if (!AutomationPredicate.structuralContainer(start) &&
         start.state[StateType.FOCUSABLE]) {