Remove m_original_source_browsing_context, m_browsing_context_name, and
m_policy_container along with their getters and setters, as they have no
callers outside the class itself.
This also adds a missing include for JS::call in WebDriver/JSON.cpp,
which was previously provided transitively through the removed headers.
Replace the custom AK JSON parser with simdjson for parsing JSON in
LibJS. This eliminates the intermediate AK::JsonValue object graph,
going directly from JSON text to JS::Value.
simdjson's on-demand API parses at ~4GB/s and only materializes values
as they are accessed, making this both faster and more memory efficient
than the previous approach.
The AK JSON parser is still used elsewhere (WebDriver protocol, config
files, etc.) but LibJS now uses simdjson exclusively for JSON.parse()
and JSON.rawJSON().
This has quite a lot of fall out. But the majority of it is just type or
UDL substitution, where the changes just fall through to other function
calls.
By changing property key storage to UTF-16, the main affected areas are:
* NativeFunction names must now be UTF-16
* Bytecode identifiers must now be UTF-16
* Module/binding names must now be UTF-16
Instead of letting every [[Call]] implementation allocate an
ExecutionContext, we now make that a responsibility of the caller.
The main point of this exercise is to allow the Call instruction
to write function arguments directly into the callee ExecutionContext
instead of copying them later.
This makes function calls significantly faster:
- 10-20% faster on micro-benchmarks (depending on argument count)
- 4% speedup on Kraken
- 2% speedup on Octane
- 5% speedup on JetStream
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
