Roll Dart SDK to 3.9.0-333.2.beta (flutter#172167)

Fixes flutter#172117

Changes since last Dart roll:

```
a4e60e5add7 Version 3.9.0-333.2.beta
071e2a7a727 [beta] Revert the http_rev back to 7d2d87e
c479b1b69b2 Version 3.9.0-333.1.beta
```

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [x] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

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[Tree Hygiene]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md
[test-exempt]:
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[Discord]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Chat.md
[Data Driven Fixes]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Data-driven-Fixes.md

Author: iinozemtsev

DEPS

@@ -56,7 +56,7 @@ vars = {
   # Dart is: https://github.com/dart-lang/sdk/blob/main/DEPS
   # You can use //tools/dart/create_updated_flutter_deps.py to produce
   # updated revision list of existing dependencies.
-  'dart_revision': '3ad640094c386c2c63be7c6a2bb3256c5ad5726c',
+  'dart_revision': 'a4e60e5add75b3d06f380aad73ca660a719fa738',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py
@@ -66,7 +66,7 @@ vars = {
   'dart_core_rev': 'b59ecf4ceebe6153e1c0166b7c9a7fdd9458a89d',
   'dart_devtools_rev': '131c9de7c067973d314b2684939c95e0a82b2bdb',
   'dart_ecosystem_rev': 'd5233c6dd0767cffa5742e32c4bc7c230c9c4b12',
-  'dart_http_rev': '4209e846100cb22d60dea7e48727334b8c55be34',
+  'dart_http_rev': '7d2d87ebfba86035a9ca6b79160ccc2ac1253c0c',
   'dart_i18n_rev': 'c45e050426bdeaaa120e5ce856abb486863d0476',
   'dart_libprotobuf_rev': '24487dd1045c7f3d64a21f38a3f0c06cc4cf2edb',
   'dart_perfetto_rev': '13ce0c9e13b0940d2476cd0cff2301708a9a2e2b',