This interface is a callback interface that allows the client to
receive detailed information about the decisions made by the migration
tool, and the source code locations associated with those decisions.
The idea is that a client of this interface can put together a report
to the user to help them understand the behavior of the migration
tool.
The instrumentation interface mostly exposes internals of the
migration engine through some safe, non-destructive interfaces. The
interface itself is documented in the new file
pkg/nnbd_migration/lib/instrumentation.dart. For examples of what
information the client can expect to receive through the
instrumentation interface, see the new file
pkg/nnbd_migration/test/instrumentation_test.dart.
Change-Id: I079551922bff75e0e8d290819f31533c29d7b62f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/117285
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Paul Berry <paulberry@google.com>
4ae145e173