Make --dart-sdk-summary required for build mode.

I ran internal presubmit, and it is green.
https://test.corp.google.com/ui#id=OCL:313462021:BASE:313498128:1590635658131:e79a9c02

Change-Id: I301a4a764d9b4641b0f29d2821ad54d8f50656f6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/149205
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
Reviewed-by: Paul Berry <paulberry@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>

https://dart.googlesource.com/sdk/+/0359275a05ffd5c908ceb742a9a0132a4f4f2227
1 file changed
tree: d56ca6a3bfa3b905a082e434e57b6e055632db51
  1. commits.json