determines whether there are currently forms available at all
If you need read access to the forms collection, then you might check
the existence of forms using hasForms, and if it returns
false, you can do as if XFormsSupplier::getForms would
have returned an empty container.
Semantically, hasForms is equivalent to calling
::XElementAccess::hasElements on the container returned by
XFormsSupplier::getForms. But when using the latter, the
implementation is forced to create a empty container, which might be potentially
expensive.
