[vm] Disable waitFor for 3.3 release

Revert "[vm] Enable waitFor for 3.2 release"

This reverts commit f8086ed78c.

R=kustermann@google.com
TEST=covered by existing tests

Bug: https://github.com/dart-lang/sdk/issues/52121
Change-Id: Ic5c7ad9af8ff142564ce237f868dd39354dfd615
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/338761
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>

CHANGELOG.md

@@ -144,6 +144,16 @@ constraint][language version] lower bound to 3.2 or greater (`sdk: '^3.2.0'`).
 
 - Added `broadcast` parameter to `Stream.empty` constructor.
 
+#### `dart:cli`
+
+- **Breaking change** [#52121][]:
+  - `waitFor` is disabled by default and slated for removal in 3.4. Attempting
+  to call this function will now throw an exception. Users that still depend
+  on `waitFor` can enable it by passing `--enable_deprecated_wait_for` flag
+  to the VM.
+
+[#52121]: https://github.com/dart-lang/sdk/issues/52121
+
 #### `dart:convert`
 
 - **Breaking change** [#52801][]:

runtime/vm/dart_api_impl.cc

@@ -84,7 +84,7 @@ DEFINE_FLAG(bool,
             "Dump common hash tables before snapshotting.");
 DEFINE_FLAG(bool,
             enable_deprecated_wait_for,
-            true,
+            false,
             "Enable deprecated dart:cli waitFor. "
             "This feature will be fully removed in Dart 3.4 release. "
             "See https://dartbug.com/52121.");