update the changelog

CHANGELOG.md

@@ -1,5 +1,40 @@
 ## Changelog
 ##### Unreleased
+- [Iterator Helpers](https://github.com/tc39/proposal-iterator-helpers) proposal:
+  - Built-ins:
+    - `Iterator`
+      - `Iterator.from`
+      - `Iterator#drop`
+      - `Iterator#every`
+      - `Iterator#filter`
+      - `Iterator#find`
+      - `Iterator#flatMap`
+      - `Iterator#forEach`
+      - `Iterator#map`
+      - `Iterator#reduce`
+      - `Iterator#some`
+      - `Iterator#take`
+      - `Iterator#toArray`
+      - `Iterator#toAsync`
+      - `Iterator#@@toStringTag`
+    - `AsyncIterator`
+      - `AsyncIterator.from`
+      - `AsyncIterator#drop`
+      - `AsyncIterator#every`
+      - `AsyncIterator#filter`
+      - `AsyncIterator#find`
+      - `AsyncIterator#flatMap`
+      - `AsyncIterator#forEach`
+      - `AsyncIterator#map`
+      - `AsyncIterator#reduce`
+      - `AsyncIterator#some`
+      - `AsyncIterator#take`
+      - `AsyncIterator#toArray`
+      - `AsyncIterator#@@toStringTag`
+  - Moved to Stage 3, [November TC39 meeting](https://github.com/babel/proposals/issues/85#issuecomment-1333474304)
+  - Added `/actual/` entries, unconditional forced replacement disabled for features that survived to Stage 3
+  - `.from` accept strings, `.flatMap` throws on strings returned from the callback, [proposal-iterator-helpers/244](https://github.com/tc39/proposal-iterator-helpers/pull/244), [proposal-iterator-helpers/250](https://github.com/tc39/proposal-iterator-helpers/pull/250)
+  - `.from` and `.flatMap` throws on non-object *iterators*, [proposal-iterator-helpers/253](https://github.com/tc39/proposal-iterator-helpers/pull/253)
 - Fixed a theoretically possible future conflict of polyfills definitions in the pure version
 - [Change `Array` by copy proposal](https://github.com/tc39/proposal-change-array-by-copy) marked as enabled by default from Deno 1.27, [deno/16429](https://github.com/denoland/deno/pull/16429)
 - Added Deno 1.28 compat data mapping