[dart2js] Ensure the _Cell constructor is called eagerly.
[dart2js] Ensure the _Cell constructor is called eagerly.

Change-Id: Ie342505a91061571fe18465e58df5f6f4ef24db7
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/195173
Reviewed-by: Stephen Adams <60cb5b73b7e0cb7dcda53302da4fab6ecfc7fa8b@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