[dart2wasm] Fix minor bug with redirecting initializers.
[dart2wasm] Fix minor bug with redirecting initializers.

Change-Id: I747ad702d2189b7c113e9202f77ad19a4b72c14a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/250580
Commit-Queue: Joshua Litt <9f8daed1ab51574c9a48ffacb03e4a1adb4f880c@google.com>
Reviewed-by: Aske Simon Christensen <589eb3fd9a84f06d0ac46d3aa71dddcfb0814ccd@google.com>

dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk