As mandated by the spec. Test 1654 is extended to verify. Closes #4443
So that users can mask in/out specific HTTP versions when Alt-Svc is used. - Removed "h2c" and updated test case accordingly - Changed how the altsvc struct is laid out - Added ifdefs to make the unittest run even in a quiche-tree Closes #4201
... to make it handle torture tests properly. Reported-by: Marcel Raad Fixes #4021 Closes #4022