Cleanup: separating Registry interface from implementation.
Cleanup: separating Registry interface from implementation.

Change-Id: I9d4d1199c36b859b5870951c85e8f0bb6c035dd0
ORIGINAL_AUTHOR=Bartosz Przydatek <przydatek@google.com>

GitOrigin-RevId: baaa74af86d9883d826b14bda18ed313868fa092

google/tink,google/tink,google/tink,google/tink,google/tink,google/tink,google/tink,google/tink