Thread UTF-16 string input through JSON, script parsing, Date parsing,
Intl option parsing, Temporal parsing, and the helper library boundaries
that feed those parsers. Preserve ASCII fast paths where the source data
is known to be ASCII.
Move the remaining LibJS primitive string users to UTF-16 views and
strings. Remove the primitive string UTF-8 accessors and byte-string
coercion paths so new callers cannot rely on the old storage model.
This reverts commit c14173f651. We
should only annotate the minimum number of symbols that external
consumers actually use, so I am starting from scratch to do that
We were previously unable to use simdutf for base64 decoding operations
other than "loose". Upstream has added support for the "strict" and
"stop-before-partial" operations, so let's make use of them!
Resulting in a massive rename across almost everywhere! Alongside the
namespace change, we now have the following names:
* JS::NonnullGCPtr -> GC::Ref
* JS::GCPtr -> GC::Ptr
* JS::HeapFunction -> GC::Function
* JS::CellImpl -> GC::Cell
* JS::Handle -> GC::Root
