Implement `AsyncLocalStorage` (#3089)

* work to get async local storage working.

* a

* a

* everything but queueMicrotask

* sdfghj

* .

* finish

* tests

* test

* ok

* done

* im so stupid

* Upgrade WebKit

* refactor

* refactor

* changes requested

* oops

* cool

* fix runInAsyncScope

1 files changed, 9 insertions, 0 deletions

diff --git a/src/js/builtins/AsyncContext.ts b/src/js/builtins/AsyncContext.ts
new file mode 100644
index 000000000..1c55feeba
--- /dev/null
+++ b/src/js/builtins/AsyncContext.ts
@@ -0,0 +1,9 @@
+// Used by async_hooks to manipulate the async context
+
+export function getAsyncContext(): ReadonlyArray<any> | undefined {
+  return $getInternalField($asyncContext, 0);
+}
+
+export function setAsyncContext(contextValue: ReadonlyArray<any> | undefined) {
+  return $putInternalField($asyncContext, 0, contextValue);
+}