This allows us to see which files were read, unlinked summary created,
how many many references to data we have, how we discard data from the
byte store, how we discard libraries from LinkedElementFactory,
and linked summaries from the byte store, etc.
Change-Id: I4eb57d96db8e1f816e7b932b727a6a92e6b07248
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/247244
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
Konstantin Shcheglov
09967d8c25