With this change, we now have ~1200 CellAllocators across both LibJS and
LibWeb in a normal WebContent instance.
This gives us a minimum heap size of 4.7 MiB in the scenario where we
only have one cell allocated per type. Of course, in practice there will
be many more of each type, so the effective overhead is quite a bit
smaller than that in practice.
I left a few types unconverted to this mechanism because I got tired of
doing this. :^)
This patch replaces the use of JS::SafeFunction for the
OnFetchScriptComplete in various script fetching functions with
JS::HeapFunction. The same applies for callbacks in ModuleMap.
This also removes DescendantFetchingContext, which stashed the
on complete function in fetch_descendants_of_a_module_script
for multiple calls to fetch_internal_module_script_graph
previously.
This will make it easier to support both string types at the same time
while we convert code, and tracking down remaining uses.
One big exception is Value::to_string() in LibJS, where the name is
dictated by the ToString AO.
We have a new, improved string type coming up in AK (OOM aware, no null
state), and while it's going to use UTF-8, the name UTF8String is a
mouthful - so let's free up the String name by renaming the existing
class.
Making the old one have an annoying name will hopefully also help with
quick adoption :^)
This patch adds the ModuleMap class used to keep track of the type and
url of a module as well as the fetching state associated. Each
environment settings object now also has a module map.
