[bazel] Fix serialization when not doing summary
[bazel] Fix serialization when not doing summary

Before this CL, if using the incremental compiler in bazels
kernel_worker, did not do summaries and did ask to "exclude-non-sources"
one would still get the entire thing (including loaded summaries etc)
(i.e. it would behave as if "exclude-non-sources" wasn't set).

This CL fixes it and makes it serialize as in the non-incremental case.

Change-Id: I396b53664a3d1ac32a243e903c8ff5c049fca453
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/113021
Commit-Queue: Jake Macdonald <28dccc213a1e50b0de348b9cb82c0229ef6b65f0@google.com>
Reviewed-by: Jake Macdonald <28dccc213a1e50b0de348b9cb82c0229ef6b65f0@google.com>

dartino/dart-sdk,dart-lang/sdk,dartino/dart-sdk,dartino/dart-sdk,dartino/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dartino/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk