Version 2.17.0-266.1.beta

Merge '2.17.0-266.0.dev' into beta
diff --git a/CHANGELOG.md b/CHANGELOG.md
index ce5d29a..c1dec5b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -188,6 +188,11 @@
   in 2018, as it doesn't work with any Dart 2.x release.
 - Add optional `sourcePort` parameter to `Socket.connect`, `Socket.startConnect`, `RawSocket.connect` and `RawSocket.startConnect`
 
+- **Breaking Change** [#45410](https://github.com/dart-lang/sdk/issues/45410):
+  `HttpClient` no longer transmits some headers (i.e. `authorization`,
+  `www-authenticate`, `cookie`, `cookie2`) when processing redirects to
+  a different domain.
+
 #### `dart:isolate`
 
 - **Breaking change** [#47769](https://github.com/dart-lang/sdk/issues/47769):
diff --git a/tools/VERSION b/tools/VERSION
index 0ec8410..349b693 100644
--- a/tools/VERSION
+++ b/tools/VERSION
@@ -23,9 +23,9 @@
 #  * Making cherry-picks to stable channel
 #     - increase PATCH by 1
 #
-CHANNEL dev
+CHANNEL beta
 MAJOR 2
 MINOR 17
 PATCH 0
 PRERELEASE 266
-PRERELEASE_PATCH 0
\ No newline at end of file
+PRERELEASE_PATCH 1
\ No newline at end of file