Drop out of font registration when unable to get file content
Drop out of font registration when unable to get file content

Closes #1097

nathanntg/dompdf,BrunoDeBarros/dompdf,BrunoDeBarros/dompdf,IvoPereira/dompdf,nathanntg/dompdf,edge-soft/dompdf,dompdf/dompdf,dompdf/dompdf,IvoPereira/dompdf,edge-soft/dompdf,IvoPereira/dompdf