* Bookmarkable if the {@link ObjectAction action} has a {@link BookmarkPolicyFacet bookmark} policy
* of {@link BookmarkPolicy#AS_ROOT root}, and has safe {@link ObjectAction#getSemantics() semantics}.
*/
public boolean isBookmarkable() {
final ObjectAction action = getActionMemento().getAction();
final BookmarkPolicyFacet bookmarkPolicy = action.getFacet(BookmarkPolicyFacet.class);
final boolean safeSemantics = action.getSemantics() == ActionSemantics.Of.SAFE;
return bookmarkPolicy.value() == BookmarkPolicy.AS_ROOT && safeSemantics;
}