coverity#1209860 try and silence Untrusted loop bound warning

we kind of have to trust this data

Change-Id: I1b74f8ad95008f5e759fd2267c879091edc5d58e
coverity#1222238 Untrusted loop bound

Change-Id: I1a4dec8727d0a27f7fd0396fd22d955f61daaee4
coverity#1242573 Untrusted loop bound

Change-Id: Id2847c55ccab7272919e76542bc0e0570bc9af12
coverity#1242573 Untrusted loop bound

Change-Id: Ic84e57fbfa2b532409865c4364b91be594d252cf
add a regression test for .met files

OS/2 Metafile Format

aka

Presentation Manager Metafile File Format

this format appears to not to have a mime-type

Change-Id: I8b2356fb42272a6e0550abf09f46b051d22b64a5
coverity#1242582 Untrusted loop bound

Change-Id: I72d2c4979b62a025d212ce5ee3b7141c40376fa7