b0484ecbde
Restore checks against reloading a library with deferred prefixes. No loading is actually deferred. Bug: https://github.com/dart-lang/sdk/issues/26878 Bug: https://github.com/dart-lang/sdk/issues/41974 Change-Id: Iec2662de117453d596cca28dd9481a9751091ce9 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/149613 Commit-Queue: Ryan Macnak <rmacnak@google.com> Reviewed-by: Alexander Markov <alexmarkov@google.com> Reviewed-by: Siva Annamalai <asiva@google.com>