The cache content is not duplicated, like other caches, but the setting
and specified file name are.
Test 1908 is extended to verify this somewhat. Since the duplicated
handle gets the same file name, the test unfortunately overwrites the
same file twice (with different contents) which makes it hard to check
automatically.
Closes#5923
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
