Code:  bool AXObject::isHiddenForTextAlternativeCalculation() const {
  if (equalIgnoringCase(getAttribute(aria_hiddenAttr), "false"))
     return false;
 
   if (getLayoutObject())
    return getLayoutObject()->style()->visibility() != EVisibility::kVisible;

  Document* document = getDocument();
  if (!document || !document->frame())
    return false;
  if (Node* node = getNode()) {
    if (node->isConnected() && node->isElementNode()) {
      RefPtr<ComputedStyle> style =
          document->ensureStyleResolver().styleForElement(toElement(node));
      return style->display() == EDisplay::kNone ||
             style->visibility() != EVisibility::kVisible;
    }
  }
  return false;
}

Vulnerability Type: Exec Code 
CWE ID: CWE-254
Summary: Google Chrome before 44.0.2403.89 does not ensure that the auto-open list omits all dangerous file types, which makes it easier for remote attackers to execute arbitrary code by providing a crafted file and leveraging a user's previous *Always open files of this type* choice, related to download_commands.cc and download_prefs.cc.
Commit Message: Switch to equalIgnoringASCIICase throughout modules/accessibility

BUG=627682

Review-Url: https://codereview.chromium.org/2793913007
Cr-Commit-Position: refs/heads/master@{#461858}