[cfe] Use 'packageConfig' instead of 'script' in an internal tool
[cfe] Use 'packageConfig' instead of 'script' in an internal tool

Change-Id: Ibcad91ddbaeb5b466c09a55c2be31f2a705d895f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/210461
Reviewed-by: Jens Johansen <05223a3c6bdf76af6f84755eae231abeebcf4530@google.com>
Commit-Queue: Dmitry Stefantsov <95a4b7e39916a54bd6477bec6a6de014b977db32@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