Switch to equalIgnoringASCIICase throughout modules/accessibility

BUG=627682

Review-Url: https://codereview.chromium.org/2793913007
Cr-Commit-Position: refs/heads/master@{#461858}
bool roleAllowsMultiselectable(AccessibilityRole role) {
  return role == GridRole || role == ListBoxRole || role == TabListRole ||
         role == TreeGridRole || role == TreeRole;
}

bool roleAllowsMultiselectable(AccessibilityRole role) {
  return role == GridRole || role == ListBoxRole || role == TabListRole ||
         role == TreeGridRole || role == TreeRole;
}
