Switch to equalIgnoringASCIICase throughout modules/accessibility

BUG=627682

Review-Url: https://codereview.chromium.org/2793913007
Cr-Commit-Position: refs/heads/master@{#461858}
bool AXObject::isScrollableContainer() const {
  return !!getScrollableAreaIfScrollable();
}

bool AXObject::isScrollableContainer() const {
  return !!getScrollableAreaIfScrollable();
}
