Instead of spawning these processes from the WebContent process, we now
create them in the Browser chrome.
Part 1/N of "all processes are owned by the chrome".
It is currently a bit messy to pass these options along from main() to
where WebContent is actually launched. If a new flag were to be added,
there are a couple dozen files that need to be updated to pass that flag
along. With this change, the flag can just be added to the struct, set
in main(), and handled in launch_web_content_process().
This patch brings a service to handle image decompression. With it comes
security enhancement due to the process boundary. Indeed, consequences
of a potential attack is reduced as only the decoder will crash without
perturbing the WebContent process.
It also allows us to display pages containing images that we claim to
support but still make us crash, like for not-finished-yet decoders.
As an example, we can now load https://jpegxl.info/jxl-art.html without
crashing the WebContent process.
We were super inconsistent about this, with most "new" classes living in
the Ladybird namespace, while "old" ones were in the global namespace,
or even sitting in the Browser namespace.
LibTLS still can't access many parts of the web, so let's hide this
behind a flag (with all the plumbing that entails).
Hopefully this can encourage folks to improve LibTLS's algorithm support
:^).
Re-organize our helper files here a bit, to make a clearer distinction
between Qt-specific helpers and generic non-serenity helpers.
A future commit will move Lagom specific code from LibSQL to ladybird
as well, so that we can see about future generic apis for spawning
helper procesess.
The spawn_helper_process method was introduced together with
get_paths_for_helper_process but was only ever used briefly to spawn
WebContent. Other helper processes (SqlServer, headless_browser etc)
are either execed or spawned with their own helpers & custom arguments.
