8146725731
With this change untrusted `origin` header or method not allowed will return 403 and 405 respectively. Before this change it returned 200 with an empty body. Returning proper error codes helps users debug their setup and figure out what is wrong. Closes https://github.com/dart-lang/sdk/issues/34121 Change-Id: I60c75ee2e33882f98fd9a020d33d459e74febf29 Reviewed-on: https://dart-review.googlesource.com/c/69308 Commit-Queue: Jonas Jensen <jonasfj@google.com> Reviewed-by: Ryan Macnak <rmacnak@google.com>