[dart2js] Run fragment merging tests on minified and csp bots.
[dart2js] Run fragment merging tests on minified and csp bots.

Change-Id: Ie6d6ceb4baff8c06cd5031d0b26222594f3aa5cd
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/192602
Reviewed-by: Stephen Adams <60cb5b73b7e0cb7dcda53302da4fab6ecfc7fa8b@google.com>
Commit-Queue: Joshua Litt <9f8daed1ab51574c9a48ffacb03e4a1adb4f880c@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