The header-specific ABNF rules are completely ignored for now, but we
can at least extract a single header value, which at least works for
simple cases like `Location`-based redirects.
This is the way.
On a more serious note, there's no reason to keep adding ref-counted
classes to LibWeb now that the majority of classes is GC'd - it only
adds the risk of discovering some cycle down the line, and forces us to
use handles as we can't visit().
This allows us to use this:
```cpp
auto header = TRY_OR_RETURN_OOM(realm,
Infrastructure::Header::from_string_pair(name, value));
```
Instead of the somewhat unwieldly:
```cpp
auto header = Infrastructure::Header {
.name = TRY_OR_RETURN_OOM(realm, ByteBuffer::copy(name.bytes())),
.value = TRY_OR_RETURN_OOM(realm, ByteBuffer::copy(value.bytes())),
};
```
In particular, StringView::contains(char) is often used with a u32
code point. When this is done, the compiler will for some reason allow
data corruption to occur silently.
In fact, this is one of two reasons for the following OSS Fuzz issue:
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=49184
This is probably a very old bug.
In the particular case of URLParser, AK::is_url_code_point got confused:
return /* ... */ || "!$&'()*+,-./:;=?@_~"sv.contains(code_point);
If code_point is a large code point that happens to have the correct
lower bytes, AK::is_url_code_point is then convinced that the given
code point is okay, even if it is actually problematic.
This commit fixes *only* the silent data corruption due to the erroneous
conversion, and does not fully resolve OSS-Fuzz#49184.
Turns out HashTable::contains() doesn't solely use hash() for equality
checks, so the lack of a proper equals() implementation broke the check
in convert_header_names_to_a_sorted_lowercase_set() and caused duplicate
entries in header_names_set.
The Fetch spec unfortunately will cause a name clash between the Request
concept and the Request JS object - both cannot live in the Web::Fetch
namespace, and WrapperGenerator generally assumes `Web::<Name>` for
things living in the `<Name>/` subdirectory, so let's instead move infra
code into its own namespace - it already sits in a (sub-)subdirectory
anyway.
