Switch LibJS `RegExp` over to the Rust-backed `ECMAScriptRegex` APIs.
Route `new RegExp()`, regex literals, and the RegExp builtins through
the new compile and exec APIs, and stop re-validating patterns with the
deleted C++ parser on the way in. Preserve the observable error
behavior by carrying structured compile errors and backtracking-limit
failures across the FFI boundary. Cache compiled regex state and named
capture metadata on `RegExpObject` in the new representation.
Use the new API surface to simplify and speed up the builtin paths too:
share `exec_internal`, cache compiled regex pointers, keep the legacy
RegExp statics lazy, run global replace through batch `find_all`, and
optimize replace, test, split, and String helper paths. Add regression
tests for those JavaScript-visible paths.
For the web, we allow a wobbly UTF-16 encoding (i.e. lonely surrogates
are permitted). Only in a few exceptional cases do we strictly require
valid UTF-16. As such, our `validate(AllowLonelySurrogates::Yes)` calls
will always succeed. It's a wasted effort to ever make such a check.
This patch eliminates such invocations. The validation methods will now
only check for strict UTF-16, and are only invoked when needed.
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
These properties are always substrings of the RegExp input string,
and so we can store them as views and lazily construct strings if
they're actually accessed (which most of the time they aren't).
This avoids a bunch of unnecessary memory copying, saving roughly
2.1 seconds per iteration of Speedometer.
