Switch to equalIgnoringASCIICase throughout modules/accessibility

BUG=627682

Review-Url: https://codereview.chromium.org/2793913007
Cr-Commit-Position: refs/heads/master@{#461858}
bool AXListBoxOption::isParentPresentationalRole() const {
  AXObject* parent = parentObject();
  if (!parent)
    return false;

  LayoutObject* layoutObject = parent->getLayoutObject();
  if (!layoutObject)
    return false;

  if (layoutObject->isListBox() && parent->hasInheritedPresentationalRole())
    return true;

  return false;
}

bool AXListBoxOption::isParentPresentationalRole() const {
  AXObject* parent = parentObject();
  if (!parent)
    return false;

  LayoutObject* layoutObject = parent->getLayoutObject();
  if (!layoutObject)
    return false;

  if (layoutObject->isListBox() && parent->hasInheritedPresentationalRole())
    return true;

  return false;
}
