Use `hasScheme` in place of comparing against the empty string, and
`isScheme` to compare against all other schemes.
TEST=No behavior changes.
Change-Id: Ifc9fd13c6cf37933ebd4a754c4b500dedbcb291b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/231185
Reviewed-by: Kevin Moore <kevmoo@google.com>
Commit-Queue: Nate Bosch <nbosch@google.com>
Also migrate to null safety, drop unused pedantic dep
Change-Id: Ic3be5af7e7933f2bd757e9dcdda62eb5be99c5bf
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/218085
Auto-Submit: Kevin Moore <kevmoo@google.com>
Reviewed-by: Devon Carew <devoncarew@google.com>
Commit-Queue: Devon Carew <devoncarew@google.com>
Commit-Queue: Kevin Moore <kevmoo@google.com>