Code:  const AXObject* AXObject::disabledAncestor() const {
   const AtomicString& disabled = getAttribute(aria_disabledAttr);
  if (equalIgnoringCase(disabled, "true"))
     return this;
  if (equalIgnoringCase(disabled, "false"))
     return 0;
 
   if (AXObject* parent = parentObject())
    return parent->disabledAncestor();

  return 0;
}

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}