tree d552ee2ab6f86c1ea99f626bc249f9fe54244eb4
parent b0727bd6612ed13aa92e55d127e4b336f17de4b8
author Paul Berry <paulberry@google.com> 1557775431 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> 1557775431 +0000

Remove NullabilityGraph._upstream.

Its only purpose was to make NullabilityGraph.getUpstreamNodes fast to
compute, but that function was only used in unit tests anyway so there
was no need for it to be fast.  (Minor exception: it was also used in
an assert statement, but I was able to change that to
Nullabilitygraph.getUnconditionalUpstreamNodes).

Change-Id: I8be18560c2f454908eb0e31d198fd22961a89278
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/102388
Reviewed-by: Dan Rubel <danrubel@google.com>
Commit-Queue: Paul Berry <paulberry@google.com>