ZF-11707: Disabling input type="file" in a form causes
zend_file_transfer_adapter_http::isValid to enter workaround
block of code and returning false (not validating)   In
Zend_File_Transfer_Adapter_Http::isValid() there is a block with
comment: "// Workaround for a PHP error returning empty $_FILES
when form data exceeds php settings" This workaround is executed
not only when form data exceeds php settings, but also when you
submit a form with 1 disabled file element and other non file
element.  The condition for entering workarund should also check
if sttings were exceeded.  This bug is somewhat connected to:
#ZF-10279.  After submitting a form with a single file element
which is not required and disabled, and other, non file
elements, $_FILES is an empty array. Having empty array in
$_FILES, Zend_File_Transfer_Adapter_Http::_prepareFiles()
produces empty array in Zend_File_Transfer_Adapter_Http::_files.
Since $_POST is not empty (because of other, non file form
elements), condition: "if (empty($this->_fil